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The Cope Rearrangement Tutorial

Optimising the Reactants and Products

(a) Optimisation of 1,5-hexadiene with an "anti" central linkage

A 1,5-hexadiene molecule was drawn on GaussView by combination of a ethyl fragment and two vinyl fragments. After modifying the dihedral angles of the four C atoms of each end, the anti central linkage was obtained and then optimised.


1. Optimising 1,5-hexadiene (anti) using HF/3-21G

test molecule


2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000119     0.000450     YES
RMS     Force            0.000018     0.000300     YES
Maximum Displacement     0.001048     0.001800     YES
RMS     Displacement     0.000350     0.001200     YES
Predicted change in Energy=-9.131560D-08
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.5522         -DE/DX =    0.0001              !
! R2    R(1,3)                  1.0869         -DE/DX =    0.0                 !
! R3    R(1,4)                  1.0836         -DE/DX =    0.0                 !
! R4    R(1,7)                  1.5089         -DE/DX =    0.0                 !
! R5    R(2,5)                  1.0869         -DE/DX =    0.0                 !
! R6    R(2,6)                  1.0836         -DE/DX =    0.0                 !
! R7    R(2,12)                 1.5089         -DE/DX =    0.0                 !
! R8    R(7,8)                  1.3161         -DE/DX =    0.0                 !
! R9    R(7,9)                  1.077          -DE/DX =    0.0                 !
! R10   R(8,10)                 1.0734         -DE/DX =    0.0                 !
! R11   R(8,11)                 1.0746         -DE/DX =    0.0                 !
! R12   R(12,13)                1.3161         -DE/DX =    0.0                 !
! R13   R(12,14)                1.077          -DE/DX =    0.0                 !
! R14   R(13,15)                1.0734         -DE/DX =    0.0                 !
! R15   R(13,16)                1.0746         -DE/DX =    0.0                 !
! A1    A(2,1,3)              108.7763         -DE/DX =    0.0                 !
! A2    A(2,1,4)              109.0009         -DE/DX =    0.0                 !
! A3    A(2,1,7)              111.376          -DE/DX =    0.0                 !
! A4    A(3,1,4)              107.6802         -DE/DX =    0.0                 !
! A5    A(3,1,7)              109.614          -DE/DX =    0.0                 !
! A6    A(4,1,7)              110.3051         -DE/DX =    0.0                 !
! A7    A(1,2,5)              108.7763         -DE/DX =    0.0                 !
! A8    A(1,2,6)              109.0009         -DE/DX =    0.0                 !
! A9    A(1,2,12)             111.376          -DE/DX =    0.0                 !
! A10   A(5,2,6)              107.6802         -DE/DX =    0.0                 !
! A11   A(5,2,12)             109.614          -DE/DX =    0.0                 !
! A12   A(6,2,12)             110.3051         -DE/DX =    0.0                 !
! A13   A(1,7,8)              124.7582         -DE/DX =    0.0                 !
! A14   A(1,7,9)              115.539          -DE/DX =    0.0                 !
! A15   A(8,7,9)              119.6945         -DE/DX =    0.0                 !
! A16   A(7,8,10)             121.8588         -DE/DX =    0.0                 !
! A17   A(7,8,11)             121.8063         -DE/DX =    0.0                 !
! A18   A(10,8,11)            116.3346         -DE/DX =    0.0                 !
! A19   A(2,12,13)            124.7582         -DE/DX =    0.0                 !
! A20   A(2,12,14)            115.539          -DE/DX =    0.0                 !
! A21   A(13,12,14)           119.6945         -DE/DX =    0.0                 !
! A22   A(12,13,15)           121.8588         -DE/DX =    0.0                 !
! A23   A(12,13,16)           121.8063         -DE/DX =    0.0                 !
! A24   A(15,13,16)           116.3346         -DE/DX =    0.0                 !
! D1    D(3,1,2,5)             64.905          -DE/DX =    0.0                 !
! D2    D(3,1,2,6)           -177.9448         -DE/DX =    0.0                 !
! D3    D(3,1,2,12)           -56.0129         -DE/DX =    0.0                 !
! D4    D(4,1,2,5)           -177.9448         -DE/DX =    0.0                 !
! D5    D(4,1,2,6)            -60.7946         -DE/DX =    0.0                 !
! D6    D(4,1,2,12)            61.1373         -DE/DX =    0.0                 !
! D7    D(7,1,2,5)            -56.0129         -DE/DX =    0.0                 !
! D8    D(7,1,2,6)             61.1373         -DE/DX =    0.0                 !
! D9    D(7,1,2,12)          -176.9308         -DE/DX =    0.0                 !
! D10   D(2,1,7,8)           -115.1302         -DE/DX =    0.0                 !
! D11   D(2,1,7,9)             63.8155         -DE/DX =    0.0                 !
! D12   D(3,1,7,8)            124.4436         -DE/DX =    0.0                 !
! D13   D(3,1,7,9)            -56.6106         -DE/DX =    0.0                 !
! D14   D(4,1,7,8)              6.0432         -DE/DX =    0.0                 !
! D15   D(4,1,7,9)           -175.0111         -DE/DX =    0.0                 !
! D16   D(1,2,12,13)         -115.1302         -DE/DX =    0.0                 !
! D17   D(1,2,12,14)           63.8155         -DE/DX =    0.0                 !
! D18   D(5,2,12,13)          124.4436         -DE/DX =    0.0                 !
! D19   D(5,2,12,14)          -56.6106         -DE/DX =    0.0                 !
! D20   D(6,2,12,13)            6.0432         -DE/DX =    0.0                 !
! D21   D(6,2,12,14)         -175.0111         -DE/DX =    0.0                 !
! D22   D(1,7,8,10)           179.1648         -DE/DX =    0.0                 !
! D23   D(1,7,8,11)            -1.0311         -DE/DX =    0.0                 !
! D24   D(9,7,8,10)             0.2598         -DE/DX =    0.0                 !
! D25   D(9,7,8,11)          -179.9361         -DE/DX =    0.0                 !
! D26   D(2,12,13,15)         179.1648         -DE/DX =    0.0                 !
! D27   D(2,12,13,16)          -1.0311         -DE/DX =    0.0                 !
! D28   D(14,12,13,15)          0.2598         -DE/DX =    0.0                 !
! D29   D(14,12,13,16)       -179.9361         -DE/DX =    0.0                 !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


6. Key information

Linkage Job type Method Basis set Memory limit Energy Point group
Anti Optimisation to a minimum HF 3-21G 250 MB -231.69260228 a.u. C2


(b) Optimisation of 1,5-hexadiene with an "gauche" central linkage

This molecule was drawn using a similar method as in (a), but the dihedral angles were different. I expect this structure to have higher energy than the one with anti linkage in (a), because for gauche linkage the two large vinyl substituents are closer to each other and thus more sterically hindered, leading to higher energy.


1. Optimising 1,5-hexadiene (gauche) using HF/3-21G

test molecule


2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000078     0.000450     YES
RMS     Force            0.000013     0.000300     YES
Maximum Displacement     0.000823     0.001800     YES
RMS     Displacement     0.000324     0.001200     YES
Predicted change in Energy=-3.041464D-08
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.5555         -DE/DX =   -0.0001              !
! R2    R(1,3)                  1.0852         -DE/DX =    0.0                 !
! R3    R(1,4)                  1.0846         -DE/DX =    0.0                 !
! R4    R(1,7)                  1.5098         -DE/DX =    0.0                 !
! R5    R(2,5)                  1.0852         -DE/DX =    0.0                 !
! R6    R(2,6)                  1.0846         -DE/DX =    0.0                 !
! R7    R(2,12)                 1.5098         -DE/DX =    0.0                 !
! R8    R(7,8)                  1.3164         -DE/DX =    0.0                 !
! R9    R(7,9)                  1.0757         -DE/DX =    0.0                 !
! R10   R(8,10)                 1.0734         -DE/DX =    0.0                 !
! R11   R(8,11)                 1.0748         -DE/DX =    0.0                 !
! R12   R(12,13)                1.3164         -DE/DX =    0.0                 !
! R13   R(12,14)                1.0757         -DE/DX =    0.0                 !
! R14   R(13,15)                1.0734         -DE/DX =    0.0                 !
! R15   R(13,16)                1.0748         -DE/DX =    0.0                 !
! A1    A(2,1,3)              108.3062         -DE/DX =    0.0                 !
! A2    A(2,1,4)              108.7723         -DE/DX =    0.0                 !
! A3    A(2,1,7)              112.3823         -DE/DX =    0.0                 !
! A4    A(3,1,4)              107.9558         -DE/DX =    0.0                 !
! A5    A(3,1,7)              109.8661         -DE/DX =    0.0                 !
! A6    A(4,1,7)              109.4489         -DE/DX =    0.0                 !
! A7    A(1,2,5)              108.3062         -DE/DX =    0.0                 !
! A8    A(1,2,6)              108.7723         -DE/DX =    0.0                 !
! A9    A(1,2,12)             112.3823         -DE/DX =    0.0                 !
! A10   A(5,2,6)              107.9558         -DE/DX =    0.0                 !
! A11   A(5,2,12)             109.8661         -DE/DX =    0.0                 !
! A12   A(6,2,12)             109.4489         -DE/DX =    0.0                 !
! A13   A(1,7,8)              124.4233         -DE/DX =    0.0                 !
! A14   A(1,7,9)              116.0376         -DE/DX =    0.0                 !
! A15   A(8,7,9)              119.5369         -DE/DX =    0.0                 !
! A16   A(7,8,10)             121.869          -DE/DX =    0.0                 !
! A17   A(7,8,11)             121.8494         -DE/DX =    0.0                 !
! A18   A(10,8,11)            116.2813         -DE/DX =    0.0                 !
! A19   A(2,12,13)            124.4233         -DE/DX =    0.0                 !
! A20   A(2,12,14)            116.0376         -DE/DX =    0.0                 !
! A21   A(13,12,14)           119.5369         -DE/DX =    0.0                 !
! A22   A(12,13,15)           121.869          -DE/DX =    0.0                 !
! A23   A(12,13,16)           121.8494         -DE/DX =    0.0                 !
! A24   A(15,13,16)           116.2813         -DE/DX =    0.0                 !
! D1    D(3,1,2,5)           -179.4769         -DE/DX =    0.0                 !
! D2    D(3,1,2,6)             63.4318         -DE/DX =    0.0                 !
! D3    D(3,1,2,12)           -57.9202         -DE/DX =    0.0                 !
! D4    D(4,1,2,5)             63.4318         -DE/DX =    0.0                 !
! D5    D(4,1,2,6)            -53.6595         -DE/DX =    0.0                 !
! D6    D(4,1,2,12)          -175.0114         -DE/DX =    0.0                 !
! D7    D(7,1,2,5)            -57.9202         -DE/DX =    0.0                 !
! D8    D(7,1,2,6)           -175.0114         -DE/DX =    0.0                 !
! D9    D(7,1,2,12)            63.6366         -DE/DX =    0.0                 !
! D10   D(2,1,7,8)            109.4257         -DE/DX =    0.0                 !
! D11   D(2,1,7,9)            -70.0344         -DE/DX =    0.0                 !
! D12   D(3,1,7,8)           -129.912          -DE/DX =    0.0                 !
! D13   D(3,1,7,9)             50.6278         -DE/DX =    0.0                 !
! D14   D(4,1,7,8)            -11.5386         -DE/DX =    0.0                 !
! D15   D(4,1,7,9)            169.0013         -DE/DX =    0.0                 !
! D16   D(1,2,12,13)          109.4257         -DE/DX =    0.0                 !
! D17   D(1,2,12,14)          -70.0344         -DE/DX =    0.0                 !
! D18   D(5,2,12,13)         -129.912          -DE/DX =    0.0                 !
! D19   D(5,2,12,14)           50.6278         -DE/DX =    0.0                 !
! D20   D(6,2,12,13)          -11.5386         -DE/DX =    0.0                 !
! D21   D(6,2,12,14)          169.0013         -DE/DX =    0.0                 !
! D22   D(1,7,8,10)          -179.1965         -DE/DX =    0.0                 !
! D23   D(1,7,8,11)             1.0282         -DE/DX =    0.0                 !
! D24   D(9,7,8,10)             0.2459         -DE/DX =    0.0                 !
! D25   D(9,7,8,11)          -179.5294         -DE/DX =    0.0                 !
! D26   D(2,12,13,15)        -179.1965         -DE/DX =    0.0                 !
! D27   D(2,12,13,16)           1.0282         -DE/DX =    0.0                 !
! D28   D(14,12,13,15)          0.2459         -DE/DX =    0.0                 !
! D29   D(14,12,13,16)       -179.5294         -DE/DX =    0.0                 !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


6. Key information

Linkage Job type Method Basis set Memory limit Energy Point group
Gauche Optimisation to a minimum HF 3-21G 250 MB -231.69153032 a.u. C2


7. Comparison with (a)

Energy (a) Energy (b) Energy difference (b)-(a)
-231.69260228 a.u. -231.69153032 a.u. 0.00107196 a.u.

Just like that I expected, the final energy of the optimised structure with gauche linkage is higher than that with anti linkage due to the more hindered substituents. The energy difference is equal to 0.00107196 a.u.(or 0.6726656196 kcal/mol).


(c) Optimisation of lowest energy conformation of 1,5-hexadiene

From my perspective, the structures with gauche linkage should have higher energy than those with anti linkage because of the stronger hinderance between vinyl substituents, just like the result obtained from (a) and (b) above. And this is also the general trend for butane. Therefore in order to test my hypothesis, I tried to optimise another structure with gauche linkage to see if the energy is still higher than that obtained in (a).


1. Optimising 1,5-hexadiene (gauche) using HF/3-21G

test molecule



2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000030     0.000450     YES
RMS     Force            0.000008     0.000300     YES
Maximum Displacement     0.001272     0.001800     YES
RMS     Displacement     0.000469     0.001200     YES
Predicted change in Energy=-1.907270D-08
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.5532         -DE/DX =    0.0                 !
! R2    R(1,3)                  1.0836         -DE/DX =    0.0                 !
! R3    R(1,4)                  1.0867         -DE/DX =    0.0                 !
! R4    R(1,12)                 1.5093         -DE/DX =    0.0                 !
! R5    R(2,5)                  1.0872         -DE/DX =    0.0                 !
! R6    R(2,6)                  1.0844         -DE/DX =    0.0                 !
! R7    R(2,7)                  1.5085         -DE/DX =    0.0                 !
! R8    R(7,8)                  1.3163         -DE/DX =    0.0                 !
! R9    R(7,9)                  1.0751         -DE/DX =    0.0                 !
! R10   R(8,10)                 1.0735         -DE/DX =    0.0                 !
! R11   R(8,11)                 1.0748         -DE/DX =    0.0                 !
! R12   R(12,13)                1.3165         -DE/DX =    0.0                 !
! R13   R(12,14)                1.0773         -DE/DX =    0.0                 !
! R14   R(13,15)                1.0734         -DE/DX =    0.0                 !
! R15   R(13,16)                1.0745         -DE/DX =    0.0                 !
! A1    A(2,1,3)              109.191          -DE/DX =    0.0                 !
! A2    A(2,1,4)              108.4571         -DE/DX =    0.0                 !
! A3    A(2,1,12)             111.8663         -DE/DX =    0.0                 !
! A4    A(3,1,4)              107.8761         -DE/DX =    0.0                 !
! A5    A(3,1,12)             110.2825         -DE/DX =    0.0                 !
! A6    A(4,1,12)             109.0666         -DE/DX =    0.0                 !
! A7    A(1,2,5)              108.6427         -DE/DX =    0.0                 !
! A8    A(1,2,6)              109.3183         -DE/DX =    0.0                 !
! A9    A(1,2,7)              111.7764         -DE/DX =    0.0                 !
! A10   A(5,2,6)              107.5329         -DE/DX =    0.0                 !
! A11   A(5,2,7)              109.7284         -DE/DX =    0.0                 !
! A12   A(6,2,7)              109.7401         -DE/DX =    0.0                 !
! A13   A(2,7,8)              124.532          -DE/DX =    0.0                 !
! A14   A(2,7,9)              115.5484         -DE/DX =    0.0                 !
! A15   A(8,7,9)              119.9131         -DE/DX =    0.0                 !
! A16   A(7,8,10)             121.7749         -DE/DX =    0.0                 !
! A17   A(7,8,11)             121.9613         -DE/DX =    0.0                 !
! A18   A(10,8,11)            116.2638         -DE/DX =    0.0                 !
! A19   A(1,12,13)            125.0268         -DE/DX =    0.0                 !
! A20   A(1,12,14)            115.3004         -DE/DX =    0.0                 !
! A21   A(13,12,14)           119.6721         -DE/DX =    0.0                 !
! A22   A(12,13,15)           121.843          -DE/DX =    0.0                 !
! A23   A(12,13,16)           121.7798         -DE/DX =    0.0                 !
! A24   A(15,13,16)           116.3769         -DE/DX =    0.0                 !
! D1    D(3,1,2,5)           -175.8704         -DE/DX =    0.0                 !
! D2    D(3,1,2,6)             67.0538         -DE/DX =    0.0                 !
! D3    D(3,1,2,7)            -54.645          -DE/DX =    0.0                 !
! D4    D(4,1,2,5)             66.8188         -DE/DX =    0.0                 !
! D5    D(4,1,2,6)            -50.257          -DE/DX =    0.0                 !
! D6    D(4,1,2,7)           -171.9558         -DE/DX =    0.0                 !
! D7    D(12,1,2,5)           -53.5141         -DE/DX =    0.0                 !
! D8    D(12,1,2,6)          -170.5899         -DE/DX =    0.0                 !
! D9    D(12,1,2,7)            67.7114         -DE/DX =    0.0                 !
! D10   D(2,1,12,13)         -117.2463         -DE/DX =    0.0                 !
! D11   D(2,1,12,14)           62.4359         -DE/DX =    0.0                 !
! D12   D(3,1,12,13)            4.4843         -DE/DX =    0.0                 !
! D13   D(3,1,12,14)         -175.8335         -DE/DX =    0.0                 !
! D14   D(4,1,12,13)          122.7772         -DE/DX =    0.0                 !
! D15   D(4,1,12,14)          -57.5406         -DE/DX =    0.0                 !
! D16   D(1,2,7,8)            120.8433         -DE/DX =    0.0                 !
! D17   D(1,2,7,9)            -58.2268         -DE/DX =    0.0                 !
! D18   D(5,2,7,8)           -118.5622         -DE/DX =    0.0                 !
! D19   D(5,2,7,9)             62.3677         -DE/DX =    0.0                 !
! D20   D(6,2,7,8)             -0.6121         -DE/DX =    0.0                 !
! D21   D(6,2,7,9)           -179.6822         -DE/DX =    0.0                 !
! D22   D(2,7,8,10)          -179.4496         -DE/DX =    0.0                 !
! D23   D(2,7,8,11)             0.6474         -DE/DX =    0.0                 !
! D24   D(9,7,8,10)            -0.4176         -DE/DX =    0.0                 !
! D25   D(9,7,8,11)           179.6795         -DE/DX =    0.0                 !
! D26   D(1,12,13,15)         179.8587         -DE/DX =    0.0                 !
! D27   D(1,12,13,16)          -0.324          -DE/DX =    0.0                 !
! D28   D(14,12,13,15)          0.1893         -DE/DX =    0.0                 !
! D29   D(14,12,13,16)       -179.9933         -DE/DX =    0.0                 !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


6. Key information

Linkage Job type Method Basis set Memory limit Energy Point group
Gauche Optimisation to a minimum HF 3-21G Default -231.69266121 a.u. C1


7. Comparison with (a)

Energy (a) Energy (c) Energy difference (a)-(c)
-231.69260228 a.u. -231.69266121 a.u. 0.00005893 a.u.

Surprisingly in this case, the final energy of the optimised structure with gauche linkage is lower than that with anti linkage, which is opposite to my hypothesis. The energy difference is equal to 0.00005893 a.u.(or 0.0369791643 kcal/mol). Perhaps this is because for 1,5-hexadiene, there is another factor affecting the stability of conformers, that is, the π bonds of neighbouring vinyl groups may have π/π* interactions leading to extra stablisations, so there may be some particular structures with gauche linkage having lower energy than those with anti linkage. As the structure obtained in (c) has a lower energy than that in either (a) or (b), it is likely to be the lowest energy conformer of 1,5-hexadiene.


(d) Identification of optimised structures

Optimised stucture Conformer identified from Appendix 1
(a) Anti1
(b) Gauche4
(c) Gauche3


(e) Optimisation of anti2 conformer using HF/3-21G

1. Optimising 1,5-hexadiene (anti2) using HF/3-21G

test molecule


2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000121     0.000450     YES
RMS     Force            0.000018     0.000300     YES
Maximum Displacement     0.000593     0.001800     YES
RMS     Displacement     0.000192     0.001200     YES
Predicted change in Energy=-1.010799D-07
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.5526         -DE/DX =    0.0001              !
! R2    R(1,3)                  1.0856         -DE/DX =    0.0                 !
! R3    R(1,4)                  1.0848         -DE/DX =    0.0                 !
! R4    R(1,7)                  1.509          -DE/DX =    0.0                 !
! R5    R(2,5)                  1.0856         -DE/DX =    0.0                 !
! R6    R(2,6)                  1.0848         -DE/DX =    0.0                 !
! R7    R(2,12)                 1.509          -DE/DX =    0.0                 !
! R8    R(7,8)                  1.3161         -DE/DX =    0.0                 !
! R9    R(7,9)                  1.0769         -DE/DX =    0.0                 !
! R10   R(8,10)                 1.0734         -DE/DX =    0.0                 !
! R11   R(8,11)                 1.0746         -DE/DX =    0.0                 !
! R12   R(12,13)                1.3161         -DE/DX =    0.0                 !
! R13   R(12,14)                1.0769         -DE/DX =    0.0                 !
! R14   R(13,15)                1.0734         -DE/DX =    0.0                 !
! R15   R(13,16)                1.0746         -DE/DX =    0.0                 !
! A1    A(2,1,3)              108.3477         -DE/DX =    0.0                 !
! A2    A(2,1,4)              109.4093         -DE/DX =    0.0                 !
! A3    A(2,1,7)              111.351          -DE/DX =    0.0                 !
! A4    A(3,1,4)              107.7104         -DE/DX =    0.0                 !
! A5    A(3,1,7)              109.972          -DE/DX =    0.0                 !
! A6    A(4,1,7)              109.9636         -DE/DX =    0.0                 !
! A7    A(1,2,5)              108.3477         -DE/DX =    0.0                 !
! A8    A(1,2,6)              109.4093         -DE/DX =    0.0                 !
! A9    A(1,2,12)             111.351          -DE/DX =    0.0                 !
! A10   A(5,2,6)              107.7104         -DE/DX =    0.0                 !
! A11   A(5,2,12)             109.972          -DE/DX =    0.0                 !
! A12   A(6,2,12)             109.9636         -DE/DX =    0.0                 !
! A13   A(1,7,8)              124.8104         -DE/DX =    0.0                 !
! A14   A(1,7,9)              115.5094         -DE/DX =    0.0                 !
! A15   A(8,7,9)              119.6718         -DE/DX =    0.0                 !
! A16   A(7,8,10)             121.8643         -DE/DX =    0.0                 !
! A17   A(7,8,11)             121.822          -DE/DX =    0.0                 !
! A18   A(10,8,11)            116.3134         -DE/DX =    0.0                 !
! A19   A(2,12,13)            124.8104         -DE/DX =    0.0                 !
! A20   A(2,12,14)            115.5094         -DE/DX =    0.0                 !
! A21   A(13,12,14)           119.6718         -DE/DX =    0.0                 !
! A22   A(12,13,15)           121.8643         -DE/DX =    0.0                 !
! A23   A(12,13,16)           121.822          -DE/DX =    0.0                 !
! A24   A(15,13,16)           116.3134         -DE/DX =    0.0                 !
! D1    D(3,1,2,5)            180.0            -DE/DX =    0.0                 !
! D2    D(3,1,2,6)            -62.8281         -DE/DX =    0.0                 !
! D3    D(3,1,2,12)            58.9347         -DE/DX =    0.0                 !
! D4    D(4,1,2,5)             62.8281         -DE/DX =    0.0                 !
! D5    D(4,1,2,6)            180.0            -DE/DX =    0.0                 !
! D6    D(4,1,2,12)           -58.2372         -DE/DX =    0.0                 !
! D7    D(7,1,2,5)            -58.9347         -DE/DX =    0.0                 !
! D8    D(7,1,2,6)             58.2372         -DE/DX =    0.0                 !
! D9    D(7,1,2,12)           180.0            -DE/DX =    0.0                 !
! D10   D(2,1,7,8)            114.6503         -DE/DX =    0.0                 !
! D11   D(2,1,7,9)            -64.2825         -DE/DX =    0.0                 !
! D12   D(3,1,7,8)           -125.2392         -DE/DX =    0.0                 !
! D13   D(3,1,7,9)             55.828          -DE/DX =    0.0                 !
! D14   D(4,1,7,8)             -6.7902         -DE/DX =    0.0                 !
! D15   D(4,1,7,9)            174.277          -DE/DX =    0.0                 !
! D16   D(1,2,12,13)         -114.6503         -DE/DX =    0.0                 !
! D17   D(1,2,12,14)           64.2825         -DE/DX =    0.0                 !
! D18   D(5,2,12,13)          125.2392         -DE/DX =    0.0                 !
! D19   D(5,2,12,14)          -55.828          -DE/DX =    0.0                 !
! D20   D(6,2,12,13)            6.7902         -DE/DX =    0.0                 !
! D21   D(6,2,12,14)         -174.277          -DE/DX =    0.0                 !
! D22   D(1,7,8,10)          -179.126          -DE/DX =    0.0                 !
! D23   D(1,7,8,11)             1.1023         -DE/DX =    0.0                 !
! D24   D(9,7,8,10)            -0.2346         -DE/DX =    0.0                 !
! D25   D(9,7,8,11)          -180.0063         -DE/DX =    0.0                 !
! D26   D(2,12,13,15)         179.126          -DE/DX =    0.0                 !
! D27   D(2,12,13,16)          -1.1023         -DE/DX =    0.0                 !
! D28   D(14,12,13,15)          0.2346         -DE/DX =    0.0                 !
! D29   D(14,12,13,16)        180.0063         -DE/DX =    0.0                 !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


6. Key information

Conformer Job type Method Basis set Memory limit Energy Point group
Anti2 Optimisation to a minimum HF 3-21G Default -231.69253520 a.u. Ci


7. Comparison with Appendix 1

Energy (optimised) Energy (Appendix 1)
-231.69253520 a.u. -231.69254 a.u.

The energy is very similar for my optimised structure and the one in Appendix 1, confirming the structures are the same.


(f) Reoptimisation of anti2 conformer using B3LYP/6-31G(d)

In this section, I reoptimised the previously HF/3-21G optimised anti2 1,5-hexadiene using a better method and basis set i.e. B3LYP/6-31G(d) in order to obtain a more accurate energy minimum.


1. Optimising 1,5-hexadiene (anti2) using B3LYP/6-31G(d)

test molecule


2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000015     0.000450     YES
RMS     Force            0.000007     0.000300     YES
Maximum Displacement     0.000226     0.001800     YES
RMS     Displacement     0.000081     0.001200     YES
Predicted change in Energy=-1.602862D-08
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.5481         -DE/DX =    0.0                 !
! R2    R(1,3)                  1.0997         -DE/DX =    0.0                 !
! R3    R(1,4)                  1.098          -DE/DX =    0.0                 !
! R4    R(1,7)                  1.5042         -DE/DX =    0.0                 !
! R5    R(2,5)                  1.0997         -DE/DX =    0.0                 !
! R6    R(2,6)                  1.098          -DE/DX =    0.0                 !
! R7    R(2,12)                 1.5042         -DE/DX =    0.0                 !
! R8    R(7,8)                  1.3335         -DE/DX =    0.0                 !
! R9    R(7,9)                  1.0919         -DE/DX =    0.0                 !
! R10   R(8,10)                 1.0868         -DE/DX =    0.0                 !
! R11   R(8,11)                 1.0885         -DE/DX =    0.0                 !
! R12   R(12,13)                1.3335         -DE/DX =    0.0                 !
! R13   R(12,14)                1.0919         -DE/DX =    0.0                 !
! R14   R(13,15)                1.0868         -DE/DX =    0.0                 !
! R15   R(13,16)                1.0885         -DE/DX =    0.0                 !
! A1    A(2,1,3)              108.1899         -DE/DX =    0.0                 !
! A2    A(2,1,4)              109.6058         -DE/DX =    0.0                 !
! A3    A(2,1,7)              112.6721         -DE/DX =    0.0                 !
! A4    A(3,1,4)              106.66           -DE/DX =    0.0                 !
! A5    A(3,1,7)              109.7814         -DE/DX =    0.0                 !
! A6    A(4,1,7)              109.742          -DE/DX =    0.0                 !
! A7    A(1,2,5)              108.1899         -DE/DX =    0.0                 !
! A8    A(1,2,6)              109.6058         -DE/DX =    0.0                 !
! A9    A(1,2,12)             112.6721         -DE/DX =    0.0                 !
! A10   A(5,2,6)              106.66           -DE/DX =    0.0                 !
! A11   A(5,2,12)             109.7814         -DE/DX =    0.0                 !
! A12   A(6,2,12)             109.742          -DE/DX =    0.0                 !
! A13   A(1,7,8)              125.2867         -DE/DX =    0.0                 !
! A14   A(1,7,9)              115.7272         -DE/DX =    0.0                 !
! A15   A(8,7,9)              118.9814         -DE/DX =    0.0                 !
! A16   A(7,8,10)             121.8701         -DE/DX =    0.0                 !
! A17   A(7,8,11)             121.6516         -DE/DX =    0.0                 !
! A18   A(10,8,11)            116.4778         -DE/DX =    0.0                 !
! A19   A(2,12,13)            125.2867         -DE/DX =    0.0                 !
! A20   A(2,12,14)            115.7272         -DE/DX =    0.0                 !
! A21   A(13,12,14)           118.9814         -DE/DX =    0.0                 !
! A22   A(12,13,15)           121.8701         -DE/DX =    0.0                 !
! A23   A(12,13,16)           121.6516         -DE/DX =    0.0                 !
! A24   A(15,13,16)           116.4778         -DE/DX =    0.0                 !
! D1    D(3,1,2,5)            180.0            -DE/DX =    0.0                 !
! D2    D(3,1,2,6)            -64.0627         -DE/DX =    0.0                 !
! D3    D(3,1,2,12)            58.444          -DE/DX =    0.0                 !
! D4    D(4,1,2,5)             64.0627         -DE/DX =    0.0                 !
! D5    D(4,1,2,6)            180.0            -DE/DX =    0.0                 !
! D6    D(4,1,2,12)           -57.4932         -DE/DX =    0.0                 !
! D7    D(7,1,2,5)            -58.444          -DE/DX =    0.0                 !
! D8    D(7,1,2,6)             57.4932         -DE/DX =    0.0                 !
! D9    D(7,1,2,12)          -180.0            -DE/DX =    0.0                 !
! D10   D(2,1,7,8)            118.5282         -DE/DX =    0.0                 !
! D11   D(2,1,7,9)            -60.6754         -DE/DX =    0.0                 !
! D12   D(3,1,7,8)           -120.8235         -DE/DX =    0.0                 !
! D13   D(3,1,7,9)             59.9729         -DE/DX =    0.0                 !
! D14   D(4,1,7,8)             -3.9021         -DE/DX =    0.0                 !
! D15   D(4,1,7,9)            176.8943         -DE/DX =    0.0                 !
! D16   D(1,2,12,13)         -118.5282         -DE/DX =    0.0                 !
! D17   D(1,2,12,14)           60.6754         -DE/DX =    0.0                 !
! D18   D(5,2,12,13)          120.8235         -DE/DX =    0.0                 !
! D19   D(5,2,12,14)          -59.9729         -DE/DX =    0.0                 !
! D20   D(6,2,12,13)            3.9021         -DE/DX =    0.0                 !
! D21   D(6,2,12,14)         -176.8943         -DE/DX =    0.0                 !
! D22   D(1,7,8,10)          -179.5641         -DE/DX =    0.0                 !
! D23   D(1,7,8,11)             0.7139         -DE/DX =    0.0                 !
! D24   D(9,7,8,10)            -0.3843         -DE/DX =    0.0                 !
! D25   D(9,7,8,11)           179.8938         -DE/DX =    0.0                 !
! D26   D(2,12,13,15)         179.5641         -DE/DX =    0.0                 !
! D27   D(2,12,13,16)          -0.7139         -DE/DX =    0.0                 !
! D28   D(14,12,13,15)          0.3843         -DE/DX =    0.0                 !
! D29   D(14,12,13,16)       -179.8938         -DE/DX =    0.0                 !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


6. Key information

Conformer Job type Method Basis set Memory limit Energy Point group
Anti2 Optimisation to a minimum B3LYP 6-31G(d) Default -234.61170278 a.u. Ci


7. Comparison with (e)

Energy (HF/3-21G) Energy (B3LYP/6-31G(d)) Energy difference
-231.69253520 a.u. -234.61170278 a.u. 2.91916758 a.u.

The energy of B3LYP/6-31G(d) optimised structure is much lower than that of HF/3-21G optimised structure, and the energy difference is equal to 2.91916758 a.u.(or 1831.8068481258 kcal/mol). However, there are no visible differences between the two structures by simply looking at them on GaussView as the following is shown.

HF/3-21G B3LYP/6-31G(d)
Structure
test molecule
test molecule

Therefore we need to compare the geometric data between the two structures as the table is shown below, so as to find out the change in geometry responsible for the large energy difference.

A GaussView image of an anti2 1,5-hexadiene molecule.
Geometric parameter HF/3-21G B3LYP/6-31G(d)
C1=C2 (or C5=C6) bond length 1.31614 Å 1.33352 Å
C2-C3 (or C4=C5) bond length 1.50895 Å 1.50419 Å
C3-C4 bond length 1.55262 Å 1.54814 Å
C1=C2-C3-C4 (or C3-C4-C5=C6) dihedral angle +(or-)114.65024o +(or-)118.52823o

Overall, the geometry change is small, but the change in dihedral angles may be the main reason for the large energy difference. Perhaps for the B3LYP/6-31G(d) optimised structure, the double bonds have a better alignment with the neighbouring C-C/C-H bonds, resulting in strong σ-π conjugations and thus have a large stablisation in energy.


(g) Frequency analysis of optimised anti2 structure

The frequency analysis is the second derivative of the potential energy surface of a reaction. By looking at the vibrational frequency table, we can determine whether the former optimisation is successful or not. And it provides useful information of IR active and Raman active vibrations.


Frequency analysis of B3LYP/6-31G(d) optimised anti2 structure

1. File link
The frequency analysed file is linked to here.


2. General information


The energy is the same as that obtained in optimisation, which means the structure is correct (i.e. the same as the optimised structure).


3. Real output

Low frequencies ---  -18.7010  -11.7206    0.0009    0.0009    0.0011    1.7692
Low frequencies ---   72.7203   80.1406  120.0180


4. Vibrational frequencies


All vibrational frequencies are real and positive, indicating the molecule is fully optimised.


5. IR spectrum


The vibrational frequency table gives many vibrations that have zero IR absorption intensity and thus do not show on the IR spectrum, which is because the high symmetry of anti2 1,5-hexadiene i.e. Ci, leading to lack of dipole moment on some particular vibrations that are IR inactive.


6. Thermochemistry

Sum of electronic and zero-point Energies=           -234.469212
Sum of electronic and thermal Energies=              -234.461856
Sum of electronic and thermal Enthalpies=            -234.460912
Sum of electronic and thermal Free Energies=         -234.500821


7. Key information

Conformer Job type Method Basis set Memory limit Energy
Anti2 Frequency B3LYP 6-31G(d) Default -234.61170278 a.u.


Frequency analysis of HF/3-21G optimised anti2 structure

1. File link
The frequency analysed file is linked to here.


2. General information


The energy is the same as that obtained in optimisation, which means the structure is correct (i.e. the same as the optimised structure).


3. Real output

Low frequencies ---   -7.4353   -2.0270   -0.0015   -0.0014   -0.0014    2.0047
Low frequencies ---   71.1769   85.7840  116.0337

The low frequencies are within ±15 cm-1.


4. Vibrational frequencies


All vibrational frequencies are real and positive, indicating the molecule is fully optimised.


5. IR spectrum


The vibrational frequency table gives many vibrations that have zero IR absorption intensity and thus do not show on the IR spectrum, which is because the high symmetry of anti2 1,5-hexadiene i.e. Ci, leading to lack of dipole moment on some particular vibrations that are IR inactive.


6. Thermochemistry

Sum of electronic and zero-point Energies=           -231.539539
Sum of electronic and thermal Energies=              -231.532565
Sum of electronic and thermal Enthalpies=            -231.531621
Sum of electronic and thermal Free Energies=         -231.570915


7. Key information

Conformer Job type Method Basis set Memory limit Energy
Anti2 Frequency HF 3-21G Default -231.69253520 a.u.


Optimising the "Chair" and "Boat" Transition Structures

(a) Optimisation of allyl fragment

In order to build up the transition state, an optimised allyl fragment is needed, which can combine with another one in two different orientations to give the chair or boat structure.


1. Optimising allyl fragment using HF/3-21G

test molecule


2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000048     0.000450     YES
RMS     Force            0.000018     0.000300     YES
Maximum Displacement     0.000149     0.001800     YES
RMS     Displacement     0.000070     0.001200     YES
Predicted change in Energy=-1.277266D-08
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.3885         -DE/DX =    0.0                 !
! R2    R(1,3)                  1.0722         -DE/DX =    0.0                 !
! R3    R(1,4)                  1.074          -DE/DX =    0.0                 !
! R4    R(2,5)                  1.0756         -DE/DX =    0.0                 !
! R5    R(2,6)                  1.3885         -DE/DX =    0.0                 !
! R6    R(6,7)                  1.074          -DE/DX =    0.0                 !
! R7    R(6,8)                  1.0722         -DE/DX =    0.0                 !
! A1    A(2,1,3)              121.4197         -DE/DX =    0.0                 !
! A2    A(2,1,4)              121.1212         -DE/DX =    0.0                 !
! A3    A(3,1,4)              117.4591         -DE/DX =    0.0                 !
! A4    A(1,2,5)              117.8473         -DE/DX =    0.0                 !
! A5    A(1,2,6)              124.3054         -DE/DX =    0.0                 !
! A6    A(5,2,6)              117.8473         -DE/DX =    0.0                 !
! A7    A(2,6,7)              121.1212         -DE/DX =    0.0                 !
! A8    A(2,6,8)              121.4197         -DE/DX =    0.0                 !
! A9    A(7,6,8)              117.4591         -DE/DX =    0.0                 !
! D1    D(3,1,2,5)              0.0            -DE/DX =    0.0                 !
! D2    D(3,1,2,6)            180.0            -DE/DX =    0.0                 !
! D3    D(4,1,2,5)            180.0            -DE/DX =    0.0                 !
! D4    D(4,1,2,6)              0.0            -DE/DX =    0.0                 !
! D5    D(1,2,6,7)              0.0            -DE/DX =    0.0                 !
! D6    D(1,2,6,8)            180.0            -DE/DX =    0.0                 !
! D7    D(5,2,6,7)            180.0            -DE/DX =    0.0                 !
! D8    D(5,2,6,8)              0.0            -DE/DX =    0.0                 !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


6. Key information

Fragment Job type Method Basis set Memory limit Energy Point group
Allyl Optimisation to a minimum HF 3-21G Default -115.82304010 a.u. C2v


(b) Optimisation of chair transition state by computing force constants

This optimisation method is very easy and quick, but it only works well for any guess transition state that is already close enough to the exact structure.


1. Optimising chair transition state using Berny method with force constants calculation

C2h chair transition state shown in Appendix 2.
test molecule


The optimised structure looks very similar to the one in Appendix 2 on the right.


2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000059     0.000450     YES
RMS     Force            0.000016     0.000300     YES
Maximum Displacement     0.001059     0.001800     YES
RMS     Displacement     0.000295     0.001200     YES
Predicted change in Energy=-1.719612D-07
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.3893         -DE/DX =    0.0                 !
! R2    R(1,3)                  1.076          -DE/DX =    0.0                 !
! R3    R(1,4)                  1.0743         -DE/DX =    0.0                 !
! R4    R(1,12)                 2.3921         -DE/DX =    0.0                 !
! R5    R(2,5)                  1.0759         -DE/DX =    0.0                 !
! R6    R(2,6)                  1.3894         -DE/DX =   -0.0001              !
! R7    R(4,9)                  2.3918         -DE/DX =    0.0                 !
! R8    R(6,7)                  1.0742         -DE/DX =    0.0                 !
! R9    R(6,8)                  1.076          -DE/DX =    0.0                 !
! R10   R(6,15)                 2.3921         -DE/DX =    0.0                 !
! R11   R(7,14)                 2.3921         -DE/DX =    0.0                 !
! R12   R(9,10)                 1.3892         -DE/DX =    0.0                 !
! R13   R(9,11)                 1.076          -DE/DX =    0.0                 !
! R14   R(9,12)                 1.0741         -DE/DX =    0.0001              !
! R15   R(10,13)                1.0759         -DE/DX =    0.0                 !
! R16   R(10,14)                1.3893         -DE/DX =    0.0                 !
! R17   R(14,15)                1.0743         -DE/DX =    0.0                 !
! R18   R(14,16)                1.076          -DE/DX =    0.0                 !
! A1    A(2,1,3)              119.0177         -DE/DX =    0.0                 !
! A2    A(2,1,4)              118.8781         -DE/DX =    0.0                 !
! A3    A(2,1,12)              90.503          -DE/DX =    0.0                 !
! A4    A(3,1,4)              113.8221         -DE/DX =    0.0                 !
! A5    A(3,1,12)              85.538          -DE/DX =    0.0                 !
! A6    A(4,1,12)             122.638          -DE/DX =    0.0                 !
! A7    A(1,2,5)              118.198          -DE/DX =    0.0                 !
! A8    A(1,2,6)              120.4933         -DE/DX =    0.0                 !
! A9    A(5,2,6)              118.193          -DE/DX =    0.0                 !
! A10   A(1,4,9)               57.0801         -DE/DX =    0.0                 !
! A11   A(2,6,7)              118.8686         -DE/DX =    0.0                 !
! A12   A(2,6,8)              119.015          -DE/DX =    0.0                 !
! A13   A(2,6,15)              90.4821         -DE/DX =    0.0                 !
! A14   A(7,6,8)              113.8145         -DE/DX =    0.0                 !
! A15   A(7,6,15)             122.6774         -DE/DX =    0.0                 !
! A16   A(8,6,15)              85.5566         -DE/DX =    0.0                 !
! A17   A(6,7,14)              57.056          -DE/DX =    0.0                 !
! A18   A(4,9,10)              90.5059         -DE/DX =    0.0                 !
! A19   A(4,9,11)              85.5501         -DE/DX =    0.0                 !
! A20   A(4,9,12)             122.6678         -DE/DX =    0.0                 !
! A21   A(10,9,11)            119.019          -DE/DX =    0.0                 !
! A22   A(10,9,12)            118.8612         -DE/DX =    0.0                 !
! A23   A(11,9,12)            113.8138         -DE/DX =    0.0                 !
! A24   A(9,10,13)            118.1924         -DE/DX =    0.0                 !
! A25   A(9,10,14)            120.5014         -DE/DX =    0.0                 !
! A26   A(13,10,14)           118.1916         -DE/DX =    0.0                 !
! A27   A(1,12,9)              57.0668         -DE/DX =    0.0                 !
! A28   A(7,14,10)             90.4787         -DE/DX =    0.0                 !
! A29   A(7,14,15)            122.668          -DE/DX =    0.0                 !
! A30   A(7,14,16)             85.5339         -DE/DX =    0.0                 !
! A31   A(10,14,15)           118.86           -DE/DX =    0.0                 !
! A32   A(10,14,16)           119.0207         -DE/DX =    0.0                 !
! A33   A(15,14,16)           113.8381         -DE/DX =    0.0                 !
! A34   A(6,15,14)             57.0579         -DE/DX =    0.0                 !
! D1    D(3,1,2,5)             18.0655         -DE/DX =    0.0                 !
! D2    D(3,1,2,6)            177.7575         -DE/DX =    0.0                 !
! D3    D(4,1,2,5)            164.5162         -DE/DX =    0.0                 !
! D4    D(4,1,2,6)            -35.7917         -DE/DX =    0.0                 !
! D5    D(12,1,2,5)           -67.1103         -DE/DX =    0.0                 !
! D6    D(12,1,2,6)            92.5817         -DE/DX =    0.0                 !
! D7    D(2,1,4,9)            107.3365         -DE/DX =    0.0                 !
! D8    D(3,1,4,9)           -104.5532         -DE/DX =    0.0                 !
! D9    D(12,1,4,9)            -4.0796         -DE/DX =    0.0                 !
! D10   D(2,1,12,9)          -116.2747         -DE/DX =    0.0                 !
! D11   D(3,1,12,9)           124.6546         -DE/DX =    0.0                 !
! D12   D(4,1,12,9)             9.1162         -DE/DX =    0.0                 !
! D13   D(1,2,6,7)             35.8021         -DE/DX =    0.0                 !
! D14   D(1,2,6,8)           -177.7862         -DE/DX =    0.0                 !
! D15   D(1,2,6,15)           -92.6007         -DE/DX =    0.0                 !
! D16   D(5,2,6,7)           -164.5049         -DE/DX =    0.0                 !
! D17   D(5,2,6,8)            -18.0931         -DE/DX =    0.0                 !
! D18   D(5,2,6,15)            67.0924         -DE/DX =    0.0                 !
! D19   D(1,4,9,10)          -116.2667         -DE/DX =    0.0                 !
! D20   D(1,4,9,11)           124.6619         -DE/DX =    0.0                 !
! D21   D(1,4,9,12)             9.1189         -DE/DX =    0.0                 !
! D22   D(2,6,7,14)          -107.3533         -DE/DX =    0.0                 !
! D23   D(8,6,7,14)           104.5718         -DE/DX =    0.0                 !
! D24   D(15,6,7,14)            4.057          -DE/DX =    0.0                 !
! D25   D(2,6,15,14)          116.3168         -DE/DX =    0.0                 !
! D26   D(7,6,15,14)           -9.0638         -DE/DX =    0.0                 !
! D27   D(8,6,15,14)         -124.6141         -DE/DX =    0.0                 !
! D28   D(6,7,14,10)          116.2997         -DE/DX =    0.0                 !
! D29   D(6,7,14,15)           -9.0629         -DE/DX =    0.0                 !
! D30   D(6,7,14,16)         -124.6244         -DE/DX =    0.0                 !
! D31   D(4,9,10,13)          -67.0954         -DE/DX =    0.0                 !
! D32   D(4,9,10,14)           92.5996         -DE/DX =    0.0                 !
! D33   D(11,9,10,13)          18.0958         -DE/DX =    0.0                 !
! D34   D(11,9,10,14)         177.7907         -DE/DX =    0.0                 !
! D35   D(12,9,10,13)         164.5001         -DE/DX =    0.0                 !
! D36   D(12,9,10,14)         -35.805          -DE/DX =    0.0                 !
! D37   D(4,9,12,1)            -4.0822         -DE/DX =    0.0                 !
! D38   D(10,9,12,1)          107.3482         -DE/DX =    0.0                 !
! D39   D(11,9,12,1)         -104.5825         -DE/DX =    0.0                 !
! D40   D(9,10,14,7)          -92.6006         -DE/DX =    0.0                 !
! D41   D(9,10,14,15)          35.7843         -DE/DX =    0.0                 !
! D42   D(9,10,14,16)        -177.758          -DE/DX =    0.0                 !
! D43   D(13,10,14,7)          67.0945         -DE/DX =    0.0                 !
! D44   D(13,10,14,15)       -164.5206         -DE/DX =    0.0                 !
! D45   D(13,10,14,16)        -18.0629         -DE/DX =    0.0                 !
! D46   D(7,14,15,6)            4.056          -DE/DX =    0.0                 !
! D47   D(10,14,15,6)        -107.3337         -DE/DX =    0.0                 !
! D48   D(16,14,15,6)         104.553          -DE/DX =    0.0                 !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


The point group of the optimised structure is C2h, confirming the structure is correct.


6. Vibrational frequencies


As the above table is shown, there is only one imaginary frequency that has a magnitude of 818.02 cm-1. The corresponding vibrational mode is shown below, in which two nearby terminal C atoms of the two allyl fragments approach each other in a sychronised motion and facilitates a bond formation, while the other pair of terminal C atoms move away from each other in a sychronised motion and represents a bond breaking. This is exactly what happens in the Cope rearrangement, that is, one C-C bond forms and one C-C bond breaks at the same time (i.e. a concerted process) in a 6-membered ring like system.



7. Thermochemistry

Sum of electronic and zero-point Energies=           -231.466698
Sum of electronic and thermal Energies=              -231.461339
Sum of electronic and thermal Enthalpies=            -231.460395
Sum of electronic and thermal Free Energies=         -231.495203


8. Key information

Transition state type Job type Additional keywords Method Basis set Memory limit Energy Point group
Chair Optimisation to a TS (Berny), calculate the force constants once Opt=NoEigen HF 3-21G Default -231.61932237 a.u. C2h


(c) Optimisation of chair transition state using frozen coordinate method

(c)&(d) together is another way of optimisation which is more reliable and gives a better result, but more time-consuming.


1. Optimising chair transition state with frozen coordinates

A GaussView image of an optimised chair transition state with frozen coordinate.

This optimised structure looks a lot like the one optimised in (b). However, as the GaussView image is shown on the right, the optimised structure has a fixed bond distance of 2.2 Å for the terminal C atoms of the allyl fragments.


2. File link
The optimised file is linked to here.


3. General information


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000030     0.000450     YES
RMS     Force            0.000007     0.000300     YES
Maximum Displacement     0.000514     0.001800     YES
RMS     Displacement     0.000100     0.001200     YES
Predicted change in Energy=-2.609537D-07
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.381          -DE/DX =    0.0005              !
! R2    R(1,3)                  1.0742         -DE/DX =    0.0006              !
! R3    R(1,4)                  1.0728         -DE/DX =    0.0003              !
! R4    R(1,9)                  2.2112         -DE/DX =   -0.0026              !
! R5    R(1,10)                 2.794          -DE/DX =   -0.0017              !
! R6    R(1,11)                 2.6065         -DE/DX =   -0.0014              !
! R7    R(1,12)                 2.5199         -DE/DX =   -0.0014              !
! R8    R(2,5)                  1.076          -DE/DX =    0.0                 !
! R9    R(2,6)                  1.381          -DE/DX =    0.0005              !
! R10   R(2,9)                  2.794          -DE/DX =   -0.0017              !
! R11   R(2,14)                 2.7939         -DE/DX =   -0.0017              !
! R12   R(3,9)                  2.6065         -DE/DX =   -0.0014              !
! R13   R(4,9)                  2.5199         -DE/DX =   -0.0014              !
! R14   R(6,7)                  1.0728         -DE/DX =    0.0003              !
! R15   R(6,8)                  1.0742         -DE/DX =    0.0006              !
! R16   R(6,10)                 2.7939         -DE/DX =   -0.0017              !
! R17   R(6,14)                 2.2111         -DE/DX =   -0.0026              !
! R18   R(6,15)                 2.5199         -DE/DX =   -0.0014              !
! R19   R(6,16)                 2.6064         -DE/DX =   -0.0014              !
! R20   R(7,14)                 2.5199         -DE/DX =   -0.0014              !
! R21   R(8,14)                 2.6064         -DE/DX =   -0.0014              !
! R22   R(9,10)                 1.3809         -DE/DX =    0.0005              !
! R23   R(9,11)                 1.0742         -DE/DX =    0.0006              !
! R24   R(9,12)                 1.0728         -DE/DX =    0.0003              !
! R25   R(10,13)                1.076          -DE/DX =    0.0                 !
! R26   R(10,14)                1.381          -DE/DX =    0.0005              !
! R27   R(14,15)                1.0728         -DE/DX =    0.0003              !
! R28   R(14,16)                1.0742         -DE/DX =    0.0006              !
! A1    A(2,1,3)              120.0683         -DE/DX =   -0.0002              !
! A2    A(2,1,4)              119.8179         -DE/DX =   -0.0001              !
! A3    A(2,1,10)              82.4382         -DE/DX =    0.0                 !
! A4    A(2,1,11)             123.5084         -DE/DX =    0.0004              !
! A5    A(2,1,12)              88.8549         -DE/DX =    0.0                 !
! A6    A(3,1,4)              115.0816         -DE/DX =   -0.0001              !
! A7    A(3,1,10)             128.2396         -DE/DX =    0.0006              !
! A8    A(3,1,11)              86.5797         -DE/DX =    0.0002              !
! A9    A(3,1,12)              84.9819         -DE/DX =    0.0002              !
! A10   A(4,1,10)              81.9499         -DE/DX =    0.0003              !
! A11   A(4,1,11)              80.5843         -DE/DX =    0.0002              !
! A12   A(4,1,12)             118.6613         -DE/DX =    0.0006              !
! A13   A(10,1,11)             46.3535         -DE/DX =    0.0004              !
! A14   A(10,1,12)             46.8798         -DE/DX =    0.0004              !
! A15   A(11,1,12)             41.3453         -DE/DX =    0.0004              !
! A16   A(1,2,5)              118.0882         -DE/DX =    0.0                 !
! A17   A(1,2,6)              122.0681         -DE/DX =   -0.0002              !
! A18   A(1,2,14)              97.5634         -DE/DX =    0.0                 !
! A19   A(5,2,6)              118.0863         -DE/DX =    0.0                 !
! A20   A(5,2,9)              108.7359         -DE/DX =    0.0001              !
! A21   A(5,2,14)             108.7302         -DE/DX =    0.0001              !
! A22   A(6,2,9)               97.5568         -DE/DX =    0.0                 !
! A23   A(9,2,14)              51.2461         -DE/DX =    0.0005              !
! A24   A(2,6,7)              119.8147         -DE/DX =   -0.0001              !
! A25   A(2,6,8)              120.0668         -DE/DX =   -0.0002              !
! A26   A(2,6,10)              82.4415         -DE/DX =    0.0                 !
! A27   A(2,6,15)              88.8495         -DE/DX =    0.0                 !
! A28   A(2,6,16)             123.5089         -DE/DX =    0.0004              !
! A29   A(7,6,8)              115.0808         -DE/DX =   -0.0001              !
! A30   A(7,6,10)              81.9518         -DE/DX =    0.0003              !
! A31   A(7,6,15)             118.6718         -DE/DX =    0.0006              !
! A32   A(7,6,16)              80.5978         -DE/DX =    0.0002              !
! A33   A(8,6,10)             128.2454         -DE/DX =    0.0006              !
! A34   A(8,6,15)              84.9896         -DE/DX =    0.0002              !
! A35   A(8,6,16)              86.5784         -DE/DX =    0.0002              !
! A36   A(10,6,15)             46.8812         -DE/DX =    0.0004              !
! A37   A(10,6,16)             46.356          -DE/DX =    0.0004              !
! A38   A(15,6,16)             41.3459         -DE/DX =    0.0004              !
! A39   A(2,9,3)               46.3531         -DE/DX =    0.0004              !
! A40   A(2,9,4)               46.8799         -DE/DX =    0.0004              !
! A41   A(2,9,10)              82.4378         -DE/DX =    0.0                 !
! A42   A(2,9,11)             128.2377         -DE/DX =    0.0006              !
! A43   A(2,9,12)              81.9504         -DE/DX =    0.0003              !
! A44   A(3,9,4)               41.345          -DE/DX =    0.0004              !
! A45   A(3,9,10)             123.5075         -DE/DX =    0.0004              !
! A46   A(3,9,11)              86.5783         -DE/DX =    0.0002              !
! A47   A(3,9,12)              80.5853         -DE/DX =    0.0002              !
! A48   A(4,9,10)              88.8545         -DE/DX =    0.0                 !
! A49   A(4,9,11)              84.98           -DE/DX =    0.0002              !
! A50   A(4,9,12)             118.6622         -DE/DX =    0.0006              !
! A51   A(10,9,11)            120.0689         -DE/DX =   -0.0002              !
! A52   A(10,9,12)            119.8174         -DE/DX =   -0.0001              !
! A53   A(11,9,12)            115.0822         -DE/DX =   -0.0001              !
! A54   A(1,10,6)              51.2464         -DE/DX =    0.0005              !
! A55   A(1,10,13)            108.7341         -DE/DX =    0.0001              !
! A56   A(1,10,14)             97.5576         -DE/DX =    0.0                 !
! A57   A(6,10,9)              97.5638         -DE/DX =    0.0                 !
! A58   A(6,10,13)            108.7286         -DE/DX =    0.0001              !
! A59   A(9,10,13)            118.0879         -DE/DX =    0.0                 !
! A60   A(9,10,14)            122.0682         -DE/DX =   -0.0002              !
! A61   A(13,10,14)           118.0862         -DE/DX =    0.0                 !
! A62   A(2,14,7)              46.8816         -DE/DX =    0.0004              !
! A63   A(2,14,8)              46.3559         -DE/DX =    0.0004              !
! A64   A(2,14,10)             82.4408         -DE/DX =    0.0                 !
! A65   A(2,14,15)             81.9526         -DE/DX =    0.0003              !
! A66   A(2,14,16)            128.2454         -DE/DX =    0.0006              !
! A67   A(7,14,8)              41.3457         -DE/DX =    0.0004              !
! A68   A(7,14,10)             88.8491         -DE/DX =    0.0                 !
! A69   A(7,14,15)            118.6737         -DE/DX =    0.0006              !
! A70   A(7,14,16)             84.9889         -DE/DX =    0.0002              !
! A71   A(8,14,10)            123.508          -DE/DX =    0.0004              !
! A72   A(8,14,15)             80.6001         -DE/DX =    0.0002              !
! A73   A(8,14,16)             86.5786         -DE/DX =    0.0002              !
! A74   A(10,14,15)           119.8129         -DE/DX =   -0.0001              !
! A75   A(10,14,16)           120.0663         -DE/DX =   -0.0002              !
! A76   A(15,14,16)           115.0826         -DE/DX =   -0.0001              !
! D1    D(3,1,2,5)             14.1563         -DE/DX =    0.0005              !
! D2    D(3,1,2,6)            178.7583         -DE/DX =    0.0002              !
! D3    D(3,1,2,14)           130.135          -DE/DX =    0.0007              !
! D4    D(4,1,2,5)            167.8413         -DE/DX =   -0.0005              !
! D5    D(4,1,2,6)            -27.5568         -DE/DX =   -0.0008              !
! D6    D(4,1,2,14)           -76.1801         -DE/DX =   -0.0003              !
! D7    D(10,1,2,5)          -115.9806         -DE/DX =   -0.0001              !
! D8    D(10,1,2,6)            48.6213         -DE/DX =   -0.0004              !
! D9    D(10,1,2,14)           -0.002          -DE/DX =    0.0                 !
! D10   D(11,1,2,5)           -93.3396         -DE/DX =    0.0001              !
! D11   D(11,1,2,6)            71.2624         -DE/DX =   -0.0002              !
! D12   D(11,1,2,14)           22.6391         -DE/DX =    0.0002              !
! D13   D(12,1,2,5)           -69.3747         -DE/DX =    0.0003              !
! D14   D(12,1,2,6)            95.2272         -DE/DX =    0.0                 !
! D15   D(12,1,2,14)           46.6039         -DE/DX =    0.0004              !
! D16   D(2,1,10,6)           -23.7685         -DE/DX =    0.0001              !
! D17   D(2,1,10,13)         -123.1226         -DE/DX =   -0.0001              !
! D18   D(2,1,10,14)            0.004          -DE/DX =    0.0                 !
! D19   D(3,1,10,6)          -146.3768         -DE/DX =    0.0001              !
! D20   D(3,1,10,13)          114.2691         -DE/DX =    0.0                 !
! D21   D(3,1,10,14)         -122.6043         -DE/DX =    0.0001              !
! D22   D(4,1,10,6)            97.9249         -DE/DX =   -0.0001              !
! D23   D(4,1,10,13)           -1.4292         -DE/DX =   -0.0002              !
! D24   D(4,1,10,14)          121.6975         -DE/DX =   -0.0001              !
! D25   D(11,1,10,6)         -177.436          -DE/DX =    0.0                 !
! D26   D(11,1,10,13)          83.2099         -DE/DX =   -0.0001              !
! D27   D(11,1,10,14)        -153.6635         -DE/DX =   -0.0001              !
! D28   D(12,1,10,6)         -119.3173         -DE/DX =    0.0001              !
! D29   D(12,1,10,13)         141.3286         -DE/DX =    0.0                 !
! D30   D(12,1,10,14)         -95.5447         -DE/DX =    0.0001              !
! D31   D(1,2,6,7)             27.5599         -DE/DX =    0.0008              !
! D32   D(1,2,6,8)           -178.7689         -DE/DX =   -0.0002              !
! D33   D(1,2,6,10)           -48.6234         -DE/DX =    0.0004              !
! D34   D(1,2,6,15)           -95.2319         -DE/DX =    0.0                 !
! D35   D(1,2,6,16)           -71.2759         -DE/DX =    0.0002              !
! D36   D(5,2,6,7)           -167.8379         -DE/DX =    0.0005              !
! D37   D(5,2,6,8)            -14.1667         -DE/DX =   -0.0005              !
! D38   D(5,2,6,10)           115.9789         -DE/DX =    0.0001              !
! D39   D(5,2,6,15)            69.3703         -DE/DX =   -0.0003              !
! D40   D(5,2,6,16)            93.3264         -DE/DX =   -0.0001              !
! D41   D(9,2,6,7)             76.1817         -DE/DX =    0.0003              !
! D42   D(9,2,6,8)           -130.1471         -DE/DX =   -0.0007              !
! D43   D(9,2,6,10)            -0.0016         -DE/DX =    0.0                 !
! D44   D(9,2,6,15)           -46.6102         -DE/DX =   -0.0004              !
! D45   D(9,2,6,16)           -22.6541         -DE/DX =   -0.0002              !
! D46   D(5,2,9,3)             83.2092         -DE/DX =   -0.0001              !
! D47   D(5,2,9,4)            141.3276         -DE/DX =    0.0                 !
! D48   D(5,2,9,10)          -123.1238         -DE/DX =   -0.0001              !
! D49   D(5,2,9,11)           114.2682         -DE/DX =    0.0                 !
! D50   D(5,2,9,12)            -1.4309         -DE/DX =   -0.0002              !
! D51   D(6,2,9,3)           -153.6639         -DE/DX =   -0.0001              !
! D52   D(6,2,9,4)            -95.5455         -DE/DX =    0.0001              !
! D53   D(6,2,9,10)             0.0032         -DE/DX =    0.0                 !
! D54   D(6,2,9,11)          -122.6049         -DE/DX =    0.0001              !
! D55   D(6,2,9,12)           121.6961         -DE/DX =   -0.0001              !
! D56   D(14,2,9,3)          -177.436          -DE/DX =    0.0                 !
! D57   D(14,2,9,4)          -119.3176         -DE/DX =    0.0001              !
! D58   D(14,2,9,10)          -23.769          -DE/DX =    0.0001              !
! D59   D(14,2,9,11)         -146.3771         -DE/DX =    0.0001              !
! D60   D(14,2,9,12)           97.9239         -DE/DX =   -0.0001              !
! D61   D(1,2,14,7)            95.5418         -DE/DX =   -0.0001              !
! D62   D(1,2,14,8)           153.6589         -DE/DX =    0.0001              !
! D63   D(1,2,14,10)            0.004          -DE/DX =    0.0                 !
! D64   D(1,2,14,15)         -121.6829         -DE/DX =    0.0001              !
! D65   D(1,2,14,16)          122.614          -DE/DX =   -0.0001              !
! D66   D(5,2,14,7)          -141.328          -DE/DX =    0.0                 !
! D67   D(5,2,14,8)           -83.2109         -DE/DX =    0.0001              !
! D68   D(5,2,14,10)          123.1342         -DE/DX =    0.0001              !
! D69   D(5,2,14,15)            1.4472         -DE/DX =    0.0002              !
! D70   D(5,2,14,16)         -114.2559         -DE/DX =    0.0                 !
! D71   D(9,2,14,7)           119.3054         -DE/DX =   -0.0001              !
! D72   D(9,2,14,8)           177.4225         -DE/DX =    0.0                 !
! D73   D(9,2,14,10)           23.7676         -DE/DX =   -0.0001              !
! D74   D(9,2,14,15)          -97.9194         -DE/DX =    0.0001              !
! D75   D(9,2,14,16)          146.3775         -DE/DX =   -0.0001              !
! D76   D(2,6,10,1)            23.7671         -DE/DX =   -0.0001              !
! D77   D(2,6,10,9)             0.0032         -DE/DX =    0.0                 !
! D78   D(2,6,10,13)          123.1327         -DE/DX =    0.0001              !
! D79   D(7,6,10,1)           -97.9217         -DE/DX =    0.0001              !
! D80   D(7,6,10,9)          -121.6857         -DE/DX =    0.0001              !
! D81   D(7,6,10,13)            1.4438         -DE/DX =    0.0002              !
! D82   D(8,6,10,1)           146.3782         -DE/DX =   -0.0001              !
! D83   D(8,6,10,9)           122.6143         -DE/DX =   -0.0001              !
! D84   D(8,6,10,13)         -114.2562         -DE/DX =    0.0                 !
! D85   D(15,6,10,1)          119.3049         -DE/DX =   -0.0001              !
! D86   D(15,6,10,9)           95.541          -DE/DX =   -0.0001              !
! D87   D(15,6,10,13)        -141.3296         -DE/DX =    0.0                 !
! D88   D(16,6,10,1)          177.4224         -DE/DX =    0.0                 !
! D89   D(16,6,10,9)          153.6585         -DE/DX =    0.0001              !
! D90   D(16,6,10,13)         -83.212          -DE/DX =    0.0001              !
! D91   D(2,9,10,6)            -0.0016         -DE/DX =    0.0                 !
! D92   D(2,9,10,13)         -115.9785         -DE/DX =   -0.0001              !
! D93   D(2,9,10,14)           48.6228         -DE/DX =   -0.0004              !
! D94   D(3,9,10,6)            22.6395         -DE/DX =    0.0002              !
! D95   D(3,9,10,13)          -93.3374         -DE/DX =    0.0001              !
! D96   D(3,9,10,14)           71.2639         -DE/DX =   -0.0002              !
! D97   D(4,9,10,6)            46.6045         -DE/DX =    0.0004              !
! D98   D(4,9,10,13)          -69.3724         -DE/DX =    0.0003              !
! D99   D(4,9,10,14)           95.2288         -DE/DX =    0.0                 !
! D100  D(11,9,10,6)          130.133          -DE/DX =    0.0007              !
! D101  D(11,9,10,13)          14.1562         -DE/DX =    0.0005              !
! D102  D(11,9,10,14)         178.7574         -DE/DX =    0.0002              !
! D103  D(12,9,10,6)          -76.1802         -DE/DX =   -0.0003              !
! D104  D(12,9,10,13)         167.843          -DE/DX =   -0.0005              !
! D105  D(12,9,10,14)         -27.5558         -DE/DX =   -0.0008              !
! D106  D(1,10,14,2)           -0.002          -DE/DX =    0.0                 !
! D107  D(1,10,14,7)          -46.611          -DE/DX =   -0.0004              !
! D108  D(1,10,14,8)          -22.6546         -DE/DX =   -0.0002              !
! D109  D(1,10,14,15)          76.1823         -DE/DX =    0.0003              !
! D110  D(1,10,14,16)        -130.1469         -DE/DX =   -0.0007              !
! D111  D(9,10,14,2)          -48.6247         -DE/DX =    0.0004              !
! D112  D(9,10,14,7)          -95.2337         -DE/DX =    0.0                 !
! D113  D(9,10,14,8)          -71.2774         -DE/DX =    0.0002              !
! D114  D(9,10,14,15)          27.5596         -DE/DX =    0.0008              !
! D115  D(9,10,14,16)        -178.7696         -DE/DX =   -0.0002              !
! D116  D(13,10,14,2)         115.9768         -DE/DX =    0.0001              !
! D117  D(13,10,14,7)          69.3678         -DE/DX =   -0.0003              !
! D118  D(13,10,14,8)          93.3242         -DE/DX =   -0.0001              !
! D119  D(13,10,14,15)       -167.8389         -DE/DX =    0.0005              !
! D120  D(13,10,14,16)        -14.1681         -DE/DX =   -0.0005              !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


The point group of the optimised structure is C2h, confirming the structure is correct.


6. Key information

Transition state type Job type Method Basis set Memory limit Energy Point group
Chair Optimisation to a minimum HF 3-21G Default -231.61469864 a.u. C2h


(d) Reoptimisation of chair transition state with unfrozen coordinates

1. Optimising chair transition state using Berny method without force constants calculation

A GaussView image of a optimised chair transition state using the redundant coordinate editor.

As the GaussView image is shown on the right, this optimised structure looks almost the same as the one optimised in (b).


2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000027     0.000450     YES
RMS     Force            0.000008     0.000300     YES
Maximum Displacement     0.000941     0.001800     YES
RMS     Displacement     0.000181     0.001200     YES
Predicted change in Energy=-2.950432D-07
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.3893         -DE/DX =    0.0                 !
! R2    R(1,3)                  1.076          -DE/DX =    0.0                 !
! R3    R(1,4)                  1.0742         -DE/DX =    0.0                 !
! R4    R(1,9)                  2.0199         -DE/DX =    0.0                 !
! R5    R(1,10)                 2.6767         -DE/DX =    0.0                 !
! R6    R(1,11)                 2.457          -DE/DX =    0.0                 !
! R7    R(1,12)                 2.3914         -DE/DX =    0.0                 !
! R8    R(2,5)                  1.0759         -DE/DX =    0.0                 !
! R9    R(2,6)                  1.3893         -DE/DX =    0.0                 !
! R10   R(2,9)                  2.6767         -DE/DX =    0.0                 !
! R11   R(2,12)                 2.7767         -DE/DX =    0.0                 !
! R12   R(2,14)                 2.6767         -DE/DX =    0.0                 !
! R13   R(2,15)                 2.7766         -DE/DX =    0.0                 !
! R14   R(3,9)                  2.4569         -DE/DX =    0.0                 !
! R15   R(4,9)                  2.3914         -DE/DX =    0.0                 !
! R16   R(4,10)                 2.7767         -DE/DX =    0.0                 !
! R17   R(6,7)                  1.0742         -DE/DX =    0.0                 !
! R18   R(6,8)                  1.076          -DE/DX =    0.0                 !
! R19   R(6,10)                 2.6767         -DE/DX =    0.0                 !
! R20   R(6,14)                 2.0199         -DE/DX =    0.0                 !
! R21   R(6,15)                 2.3914         -DE/DX =    0.0                 !
! R22   R(6,16)                 2.4569         -DE/DX =    0.0                 !
! R23   R(7,10)                 2.7766         -DE/DX =    0.0                 !
! R24   R(7,14)                 2.3914         -DE/DX =    0.0                 !
! R25   R(8,14)                 2.457          -DE/DX =    0.0                 !
! R26   R(9,10)                 1.3893         -DE/DX =    0.0                 !
! R27   R(9,11)                 1.076          -DE/DX =    0.0                 !
! R28   R(9,12)                 1.0742         -DE/DX =    0.0                 !
! R29   R(10,13)                1.0759         -DE/DX =    0.0                 !
! R30   R(10,14)                1.3893         -DE/DX =    0.0                 !
! R31   R(14,15)                1.0742         -DE/DX =    0.0                 !
! R32   R(14,16)                1.076          -DE/DX =    0.0                 !
! A1    A(2,1,3)              118.9978         -DE/DX =    0.0                 !
! A2    A(2,1,4)              118.8761         -DE/DX =    0.0                 !
! A3    A(2,1,10)              83.7831         -DE/DX =    0.0                 !
! A4    A(2,1,11)             127.3466         -DE/DX =    0.0                 !
! A5    A(3,1,4)              113.8178         -DE/DX =    0.0                 !
! A6    A(3,1,10)             131.0861         -DE/DX =    0.0                 !
! A7    A(3,1,11)              87.1004         -DE/DX =    0.0                 !
! A8    A(3,1,12)              85.5397         -DE/DX =    0.0                 !
! A9    A(4,1,11)              82.231          -DE/DX =    0.0                 !
! A10   A(4,1,12)             122.6535         -DE/DX =    0.0                 !
! A11   A(10,1,11)             48.7986         -DE/DX =    0.0                 !
! A12   A(10,1,12)             49.2433         -DE/DX =    0.0                 !
! A13   A(11,1,12)             43.5965         -DE/DX =    0.0                 !
! A14   A(1,2,5)              118.1693         -DE/DX =    0.0                 !
! A15   A(1,2,6)              120.5081         -DE/DX =    0.0                 !
! A16   A(1,2,14)              96.2169         -DE/DX =    0.0                 !
! A17   A(1,2,15)             106.9303         -DE/DX =    0.0                 !
! A18   A(5,2,6)              118.1708         -DE/DX =    0.0                 !
! A19   A(5,2,9)              109.3554         -DE/DX =    0.0                 !
! A20   A(5,2,12)              86.755          -DE/DX =    0.0                 !
! A21   A(5,2,14)             109.354          -DE/DX =    0.0                 !
! A22   A(5,2,15)              86.7533         -DE/DX =    0.0                 !
! A23   A(6,2,9)               96.2163         -DE/DX =    0.0                 !
! A24   A(6,2,12)             106.9315         -DE/DX =    0.0                 !
! A25   A(9,2,14)              53.5714         -DE/DX =    0.0                 !
! A26   A(9,2,15)              59.4629         -DE/DX =    0.0                 !
! A27   A(12,2,14)             59.4631         -DE/DX =    0.0                 !
! A28   A(12,2,15)             54.8235         -DE/DX =    0.0                 !
! A29   A(2,6,7)              118.877          -DE/DX =    0.0                 !
! A30   A(2,6,8)              118.9972         -DE/DX =    0.0                 !
! A31   A(2,6,10)              83.7837         -DE/DX =    0.0                 !
! A32   A(2,6,16)             127.3461         -DE/DX =    0.0                 !
! A33   A(7,6,8)              113.8153         -DE/DX =    0.0                 !
! A34   A(7,6,15)             122.6532         -DE/DX =    0.0                 !
! A35   A(7,6,16)              82.2318         -DE/DX =    0.0                 !
! A36   A(8,6,10)             131.0929         -DE/DX =    0.0                 !
! A37   A(8,6,15)              85.549          -DE/DX =    0.0                 !
! A38   A(8,6,16)              87.1031         -DE/DX =    0.0                 !
! A39   A(10,6,15)             49.2429         -DE/DX =    0.0                 !
! A40   A(10,6,16)             48.7998         -DE/DX =    0.0                 !
! A41   A(15,6,16)             43.5978         -DE/DX =    0.0                 !
! A42   A(2,9,3)               48.7994         -DE/DX =    0.0                 !
! A43   A(2,9,4)               49.2428         -DE/DX =    0.0                 !
! A44   A(2,9,10)              83.7826         -DE/DX =    0.0                 !
! A45   A(2,9,11)             131.0915         -DE/DX =    0.0                 !
! A46   A(3,9,4)               43.5979         -DE/DX =    0.0                 !
! A47   A(3,9,10)             127.3474         -DE/DX =    0.0                 !
! A48   A(3,9,11)              87.1048         -DE/DX =    0.0                 !
! A49   A(3,9,12)              82.2295         -DE/DX =    0.0                 !
! A50   A(4,9,11)              85.5456         -DE/DX =    0.0                 !
! A51   A(4,9,12)             122.6531         -DE/DX =    0.0                 !
! A52   A(10,9,11)            118.9966         -DE/DX =    0.0                 !
! A53   A(10,9,12)            118.8773         -DE/DX =    0.0                 !
! A54   A(11,9,12)            113.8152         -DE/DX =    0.0                 !
! A55   A(1,10,6)              53.5714         -DE/DX =    0.0                 !
! A56   A(1,10,7)              59.4635         -DE/DX =    0.0                 !
! A57   A(1,10,13)            109.3556         -DE/DX =    0.0                 !
! A58   A(1,10,14)             96.2161         -DE/DX =    0.0                 !
! A59   A(4,10,6)              59.4628         -DE/DX =    0.0                 !
! A60   A(4,10,7)              54.8237         -DE/DX =    0.0                 !
! A61   A(4,10,13)             86.7552         -DE/DX =    0.0                 !
! A62   A(4,10,14)            106.9309         -DE/DX =    0.0                 !
! A63   A(6,10,9)              96.2174         -DE/DX =    0.0                 !
! A64   A(6,10,13)            109.3525         -DE/DX =    0.0                 !
! A65   A(7,10,9)             106.9314         -DE/DX =    0.0                 !
! A66   A(7,10,13)             86.7516         -DE/DX =    0.0                 !
! A67   A(9,10,13)            118.1708         -DE/DX =    0.0                 !
! A68   A(9,10,14)            120.5081         -DE/DX =    0.0                 !
! A69   A(13,10,14)           118.1691         -DE/DX =    0.0                 !
! A70   A(2,14,7)              49.2435         -DE/DX =    0.0                 !
! A71   A(2,14,8)              48.7988         -DE/DX =    0.0                 !
! A72   A(2,14,10)             83.784          -DE/DX =    0.0                 !
! A73   A(2,14,16)            131.0869         -DE/DX =    0.0                 !
! A74   A(7,14,8)              43.5964         -DE/DX =    0.0                 !
! A75   A(7,14,15)            122.6545         -DE/DX =    0.0                 !
! A76   A(7,14,16)             85.5425         -DE/DX =    0.0                 !
! A77   A(8,14,10)            127.3449         -DE/DX =    0.0                 !
! A78   A(8,14,15)             82.2341         -DE/DX =    0.0                 !
! A79   A(8,14,16)             87.0983         -DE/DX =    0.0                 !
! A80   A(10,14,15)           118.8758         -DE/DX =    0.0                 !
! A81   A(10,14,16)           118.9984         -DE/DX =    0.0                 !
! A82   A(15,14,16)           113.818          -DE/DX =    0.0                 !
! D1    D(3,1,2,5)             18.1822         -DE/DX =    0.0                 !
! D2    D(3,1,2,6)            177.7564         -DE/DX =    0.0                 !
! D3    D(3,1,2,14)           134.0623         -DE/DX =    0.0                 !
! D4    D(3,1,2,15)           113.6826         -DE/DX =    0.0                 !
! D5    D(4,1,2,5)            164.5836         -DE/DX =    0.0                 !
! D6    D(4,1,2,6)            -35.8423         -DE/DX =    0.0                 !
! D7    D(4,1,2,14)           -79.5363         -DE/DX =    0.0                 !
! D8    D(4,1,2,15)           -99.9161         -DE/DX =    0.0                 !
! D9    D(10,1,2,5)          -115.8813         -DE/DX =    0.0                 !
! D10   D(10,1,2,6)            43.6928         -DE/DX =    0.0                 !
! D11   D(10,1,2,14)           -0.0012         -DE/DX =    0.0                 !
! D12   D(10,1,2,15)          -20.381          -DE/DX =    0.0                 !
! D13   D(11,1,2,5)           -92.3169         -DE/DX =    0.0                 !
! D14   D(11,1,2,6)            67.2573         -DE/DX =    0.0                 !
! D15   D(11,1,2,14)           23.5632         -DE/DX =    0.0                 !
! D16   D(11,1,2,15)            3.1835         -DE/DX =    0.0                 !
! D17   D(2,1,10,6)           -22.5778         -DE/DX =    0.0                 !
! D18   D(2,1,10,7)           -48.8671         -DE/DX =    0.0                 !
! D19   D(2,1,10,13)         -122.7886         -DE/DX =    0.0                 !
! D20   D(2,1,10,14)            0.0024         -DE/DX =    0.0                 !
! D21   D(3,1,10,6)          -146.082          -DE/DX =    0.0                 !
! D22   D(3,1,10,7)          -172.3714         -DE/DX =    0.0                 !
! D23   D(3,1,10,13)          113.7072         -DE/DX =    0.0                 !
! D24   D(3,1,10,14)         -123.5018         -DE/DX =    0.0                 !
! D25   D(11,1,10,6)         -177.5912         -DE/DX =    0.0                 !
! D26   D(11,1,10,7)          156.1194         -DE/DX =    0.0                 !
! D27   D(11,1,10,13)          82.198          -DE/DX =    0.0                 !
! D28   D(11,1,10,14)        -155.0111         -DE/DX =    0.0                 !
! D29   D(12,1,10,6)         -118.6663         -DE/DX =    0.0                 !
! D30   D(12,1,10,7)         -144.9557         -DE/DX =    0.0                 !
! D31   D(12,1,10,13)         141.1229         -DE/DX =    0.0                 !
! D32   D(12,1,10,14)         -96.0861         -DE/DX =    0.0                 !
! D33   D(1,2,6,7)             35.8386         -DE/DX =    0.0                 !
! D34   D(1,2,6,8)           -177.765          -DE/DX =    0.0                 !
! D35   D(1,2,6,10)           -43.693          -DE/DX =    0.0                 !
! D36   D(1,2,6,16)           -67.2627         -DE/DX =    0.0                 !
! D37   D(5,2,6,7)           -164.5875         -DE/DX =    0.0                 !
! D38   D(5,2,6,8)            -18.1911         -DE/DX =    0.0                 !
! D39   D(5,2,6,10)           115.8808         -DE/DX =    0.0                 !
! D40   D(5,2,6,16)            92.3112         -DE/DX =    0.0                 !
! D41   D(9,2,6,7)             79.5305         -DE/DX =    0.0                 !
! D42   D(9,2,6,8)           -134.073          -DE/DX =    0.0                 !
! D43   D(9,2,6,10)            -0.0011         -DE/DX =    0.0                 !
! D44   D(9,2,6,16)           -23.5707         -DE/DX =    0.0                 !
! D45   D(12,2,6,7)            99.9088         -DE/DX =    0.0                 !
! D46   D(12,2,6,8)          -113.6948         -DE/DX =    0.0                 !
! D47   D(12,2,6,10)           20.3771         -DE/DX =    0.0                 !
! D48   D(12,2,6,16)           -3.1925         -DE/DX =    0.0                 !
! D49   D(5,2,9,3)             82.1946         -DE/DX =    0.0                 !
! D50   D(5,2,9,4)            141.1213         -DE/DX =    0.0                 !
! D51   D(5,2,9,10)          -122.7908         -DE/DX =    0.0                 !
! D52   D(5,2,9,11)           113.7046         -DE/DX =    0.0                 !
! D53   D(6,2,9,3)           -155.0125         -DE/DX =    0.0                 !
! D54   D(6,2,9,4)            -96.0857         -DE/DX =    0.0                 !
! D55   D(6,2,9,10)             0.0021         -DE/DX =    0.0                 !
! D56   D(6,2,9,11)          -123.5024         -DE/DX =    0.0                 !
! D57   D(14,2,9,3)          -177.5926         -DE/DX =    0.0                 !
! D58   D(14,2,9,4)          -118.6659         -DE/DX =    0.0                 !
! D59   D(14,2,9,10)          -22.578          -DE/DX =    0.0                 !
! D60   D(14,2,9,11)         -146.0825         -DE/DX =    0.0                 !
! D61   D(15,2,9,3)           156.1179         -DE/DX =    0.0                 !
! D62   D(15,2,9,4)          -144.9554         -DE/DX =    0.0                 !
! D63   D(15,2,9,10)          -48.8675         -DE/DX =    0.0                 !
! D64   D(15,2,9,11)         -172.372          -DE/DX =    0.0                 !
! D65   D(9,2,12,1)           -51.7445         -DE/DX =    0.0                 !
! D66   D(1,2,14,7)            96.0846         -DE/DX =    0.0                 !
! D67   D(1,2,14,8)           155.0091         -DE/DX =    0.0                 !
! D68   D(1,2,14,10)            0.0024         -DE/DX =    0.0                 !
! D69   D(1,2,14,16)          123.5086         -DE/DX =    0.0                 !
! D70   D(5,2,14,7)          -141.1243         -DE/DX =    0.0                 !
! D71   D(5,2,14,8)           -82.1998         -DE/DX =    0.0                 !
! D72   D(5,2,14,10)          122.7935         -DE/DX =    0.0                 !
! D73   D(5,2,14,16)         -113.7003         -DE/DX =    0.0                 !
! D74   D(9,2,14,7)           118.6602         -DE/DX =    0.0                 !
! D75   D(9,2,14,8)           177.5847         -DE/DX =    0.0                 !
! D76   D(9,2,14,10)           22.5779         -DE/DX =    0.0                 !
! D77   D(9,2,14,16)          146.0842         -DE/DX =    0.0                 !
! D78   D(12,2,14,7)          144.949          -DE/DX =    0.0                 !
! D79   D(12,2,14,8)         -156.1265         -DE/DX =    0.0                 !
! D80   D(12,2,14,10)          48.8667         -DE/DX =    0.0                 !
! D81   D(12,2,14,16)         172.373          -DE/DX =    0.0                 !
! D82   D(1,4,9,10)          -116.2603         -DE/DX =    0.0                 !
! D83   D(2,6,10,1)            22.5779         -DE/DX =    0.0                 !
! D84   D(2,6,10,4)            48.8668         -DE/DX =    0.0                 !
! D85   D(2,6,10,9)             0.0021         -DE/DX =    0.0                 !
! D86   D(2,6,10,13)          122.7946         -DE/DX =    0.0                 !
! D87   D(8,6,10,1)           146.0849         -DE/DX =    0.0                 !
! D88   D(8,6,10,4)           172.3738         -DE/DX =    0.0                 !
! D89   D(8,6,10,9)           123.5092         -DE/DX =    0.0                 !
! D90   D(8,6,10,13)         -113.6983         -DE/DX =    0.0                 !
! D91   D(15,6,10,1)          118.6598         -DE/DX =    0.0                 !
! D92   D(15,6,10,4)          144.9487         -DE/DX =    0.0                 !
! D93   D(15,6,10,9)           96.084          -DE/DX =    0.0                 !
! D94   D(15,6,10,13)        -141.1234         -DE/DX =    0.0                 !
! D95   D(16,6,10,1)          177.5861         -DE/DX =    0.0                 !
! D96   D(16,6,10,4)         -156.125          -DE/DX =    0.0                 !
! D97   D(16,6,10,9)          155.0103         -DE/DX =    0.0                 !
! D98   D(16,6,10,13)         -82.1971         -DE/DX =    0.0                 !
! D99   D(14,6,15,2)         -116.2658         -DE/DX =    0.0                 !
! D100  D(6,7,10,14)          -51.7402         -DE/DX =    0.0                 !
! D101  D(2,9,10,6)            -0.0011         -DE/DX =    0.0                 !
! D102  D(2,9,10,7)           -20.3807         -DE/DX =    0.0                 !
! D103  D(2,9,10,13)         -115.8803         -DE/DX =    0.0                 !
! D104  D(2,9,10,14)           43.6931         -DE/DX =    0.0                 !
! D105  D(3,9,10,6)            23.5628         -DE/DX =    0.0                 !
! D106  D(3,9,10,7)             3.1832         -DE/DX =    0.0                 !
! D107  D(3,9,10,13)          -92.3164         -DE/DX =    0.0                 !
! D108  D(3,9,10,14)           67.257          -DE/DX =    0.0                 !
! D109  D(11,9,10,6)          134.0682         -DE/DX =    0.0                 !
! D110  D(11,9,10,7)          113.6885         -DE/DX =    0.0                 !
! D111  D(11,9,10,13)          18.189          -DE/DX =    0.0                 !
! D112  D(11,9,10,14)         177.7623         -DE/DX =    0.0                 !
! D113  D(12,9,10,6)          -79.5361         -DE/DX =    0.0                 !
! D114  D(12,9,10,7)          -99.9157         -DE/DX =    0.0                 !
! D115  D(12,9,10,13)         164.5847         -DE/DX =    0.0                 !
! D116  D(12,9,10,14)         -35.8419         -DE/DX =    0.0                 !
! D117  D(1,10,14,2)           -0.0012         -DE/DX =    0.0                 !
! D118  D(1,10,14,8)          -23.5715         -DE/DX =    0.0                 !
! D119  D(1,10,14,15)          79.5312         -DE/DX =    0.0                 !
! D120  D(1,10,14,16)        -134.0665         -DE/DX =    0.0                 !
! D121  D(4,10,14,2)           20.3771         -DE/DX =    0.0                 !
! D122  D(4,10,14,8)           -3.1931         -DE/DX =    0.0                 !
! D123  D(4,10,14,15)          99.9095         -DE/DX =    0.0                 !
! D124  D(4,10,14,16)        -113.6881         -DE/DX =    0.0                 !
! D125  D(9,10,14,2)          -43.6936         -DE/DX =    0.0                 !
! D126  D(9,10,14,8)          -67.2639         -DE/DX =    0.0                 !
! D127  D(9,10,14,15)          35.8388         -DE/DX =    0.0                 !
! D128  D(9,10,14,16)        -177.7589         -DE/DX =    0.0                 !
! D129  D(13,10,14,2)         115.8801         -DE/DX =    0.0                 !
! D130  D(13,10,14,8)          92.3099         -DE/DX =    0.0                 !
! D131  D(13,10,14,15)       -164.5875         -DE/DX =    0.0                 !
! D132  D(13,10,14,16)        -18.1852         -DE/DX =    0.0                 !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


The point group of the optimised structure is C2h, confirming the structure is correct.


6. Vibrational frequencies


Smilarly to (b), there is also only one imaginary frequency of about -818 cm-1. The corresponding vibrational mode is shown above, and the motion is similar to that of the structure obtained in (b).


7. Thermochemistry

Sum of electronic and zero-point Energies=           -231.466696
Sum of electronic and thermal Energies=              -231.461337
Sum of electronic and thermal Enthalpies=            -231.460392
Sum of electronic and thermal Free Energies=         -231.495201


8. Key information

Transition state type Job type Method Basis set Memory limit Energy Point group
Chair Optimisation to a TS (Berny) HF 3-21G Default -231.61932200 a.u. C2h


9. Comparison to (b)

Bond forming/breaking distances (b) Bond forming/breaking distances (d)
2.02038 Å 2.01990 Å

The bond forming/breaking distances of the optimised structure using the redundant coordinate editor are just slightly lower than that of the optimised structure by computing the force constants.


(e) Optimisation of boat transition state using QST2 method

First optimisation from optimised anti2 1,5-hexadiene

1. Optimising boat transition state from optimised anti2 1,5-hexadiene


The QST2 method does not give the correct boat structure using these reactant and product structures shown above. The optimisation failed and we obtained the structure shown below which looks a bit like the chair transition state but more dissociated.


test molecule


2. File link
The optimised file is linked to here.


3. General information


The gradient is larger than 0.001, which means the optimisation is not complete.


4. Symmetry information


The point group of the optimised structure is C2, indicating the structure is incorrect.


5. Key information

Transition state type Job type Method Basis set Memory limit Energy Point group
Chair-like Optimisation to a TS (QST2) HF 3-21G Default -231.54683483 a.u. C2


Second optimisation from modified reactant and product

1. Optimising boat transition state from modified reactant and product


As the above GaussView image is shown, the reactant and product structures are modified to become closer to the boat transition state so that it is easier to obtain the correct boat structure.


C2v boat transition state shown in Appendix 2.
test molecule


The optimised structure shown above is boat-like and is very similar to the one in Appendix 2 shown on the right.


2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000133     0.000450     YES
RMS     Force            0.000034     0.000300     YES
Maximum Displacement     0.001256     0.001800     YES
RMS     Displacement     0.000270     0.001200     YES
Predicted change in Energy=-2.879547D-07
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition        TS        Reactant  Product Derivative Info.         !
--------------------------------------------------------------------------------
! R1    R(1,2)             1.3815    1.3161    1.509  -DE/DX =    0.0          !
! R2    R(1,6)             2.1404    3.2253    1.5526 -DE/DX =   -0.0001       !
! R3    R(1,7)             1.0739    1.0734    1.0856 -DE/DX =    0.0          !
! R4    R(1,12)            1.0742    1.0746    1.0848 -DE/DX =    0.0          !
! R5    R(2,3)             1.3813    1.509     1.3161 -DE/DX =   -0.0001       !
! R6    R(2,8)             1.0764    1.0769    1.0769 -DE/DX =    0.0          !
! R7    R(3,4)             2.1418    1.5526    3.2253 -DE/DX =    0.0001       !
! R8    R(3,13)            1.0739    1.0856    1.0734 -DE/DX =    0.0          !
! R9    R(3,14)            1.0742    1.0848    1.0746 -DE/DX =    0.0          !
! R10   R(4,5)             1.3813    1.509     1.3161 -DE/DX =   -0.0001       !
! R11   R(4,15)            1.0742    1.0848    1.0746 -DE/DX =    0.0          !
! R12   R(4,16)            1.0739    1.0856    1.0734 -DE/DX =    0.0          !
! R13   R(5,6)             1.3815    1.3161    1.509  -DE/DX =    0.0          !
! R14   R(5,9)             1.0764    1.0769    1.0769 -DE/DX =    0.0          !
! R15   R(6,10)            1.0742    1.0746    1.0848 -DE/DX =    0.0          !
! R16   R(6,11)            1.0739    1.0734    1.0856 -DE/DX =    0.0          !
! A1    A(2,1,6)         103.3627   64.1277  100.0    -DE/DX =    0.0          !
! A2    A(2,1,7)         119.6476  121.8643  112.7378 -DE/DX =    0.0          !
! A3    A(2,1,12)        118.859   121.822   112.8447 -DE/DX =    0.0          !
! A4    A(6,1,7)         101.0441   98.0896  111.2032 -DE/DX =    0.0          !
! A5    A(6,1,12)         91.3879  108.832   112.3204 -DE/DX =    0.0          !
! A6    A(7,1,12)        114.7026  116.3134  107.7104 -DE/DX =    0.0          !
! A7    A(1,2,3)         121.6901  124.8104  124.8104 -DE/DX =    0.0          !
! A8    A(1,2,8)         117.464   119.6718  115.5094 -DE/DX =    0.0          !
! A9    A(3,2,8)         117.4633  115.5094  119.6718 -DE/DX =    0.0          !
! A10   A(2,3,4)         103.336    100.0     64.1277 -DE/DX =    0.0          !
! A11   A(2,3,13)        119.6576  112.7378  121.8643 -DE/DX =    0.0          !
! A12   A(2,3,14)        118.8859  112.8447  121.822  -DE/DX =    0.0          !
! A13   A(4,3,13)        101.0147  111.2032   98.0896 -DE/DX =    0.0          !
! A14   A(4,3,14)         91.3529  112.3204  108.832  -DE/DX =    0.0          !
! A15   A(13,3,14)       114.7123  107.7104  116.3134 -DE/DX =    0.0          !
! A16   A(3,4,5)         103.336   100.0      64.1277 -DE/DX =    0.0          !
! A17   A(3,4,15)         91.3529  112.3204  108.832  -DE/DX =    0.0          !
! A18   A(3,4,16)        101.0147  111.2032   98.0896 -DE/DX =    0.0          !
! A19   A(5,4,15)        118.8859  112.8447  121.822  -DE/DX =    0.0          !
! A20   A(5,4,16)        119.6576  112.7378  121.8643 -DE/DX =    0.0          !
! A21   A(15,4,16)       114.7123  107.7104  116.3134 -DE/DX =    0.0          !
! A22   A(4,5,6)         121.6901  124.8104  124.8104 -DE/DX =    0.0          !
! A23   A(4,5,9)         117.4633  115.5094  119.6718 -DE/DX =    0.0          !
! A24   A(6,5,9)         117.464   119.6718  115.5094 -DE/DX =    0.0          !
! A25   A(1,6,5)         103.3627   64.1277  100.0    -DE/DX =    0.0          !
! A26   A(1,6,10)         91.3879  108.832   112.3204 -DE/DX =    0.0          !
! A27   A(1,6,11)        101.0441   98.0896  111.2032 -DE/DX =    0.0          !
! A28   A(5,6,10)        118.859   121.822   112.8447 -DE/DX =    0.0          !
! A29   A(5,6,11)        119.6476  121.8643  112.7378 -DE/DX =    0.0          !
! A30   A(10,6,11)       114.7026  116.3134  107.7104 -DE/DX =    0.0          !
! D1    D(6,1,2,3)        64.8318   95.8625  114.6503 -DE/DX =    0.0          !
! D2    D(6,1,2,8)       -93.873   -83.0289  -64.2825 -DE/DX =    0.0          !
! D3    D(7,1,2,3)       176.0402  179.126  -127.1791 -DE/DX =    0.0          !
! D4    D(7,1,2,8)        17.3354    0.2346   53.8882 -DE/DX =    0.0001       !
! D5    D(12,1,2,3)      -34.3366   -1.1023   -4.8714 -DE/DX =   -0.0001       !
! D6    D(12,1,2,8)      166.9586 -179.9937  176.1959 -DE/DX =    0.0          !
! D7    D(2,1,6,5)         0.0       0.0       0.0    -DE/DX =    0.0          !
! D8    D(2,1,6,10)     -120.1316 -116.9853 -119.9037 -DE/DX =    0.0          !
! D9    D(2,1,6,11)      124.3597  121.5795  119.2998 -DE/DX =    0.0          !
! D10   D(7,1,6,5)      -124.3597 -121.5795 -119.2998 -DE/DX =    0.0          !
! D11   D(7,1,6,10)      115.5087  121.4353  120.7965 -DE/DX =    0.0          !
! D12   D(7,1,6,11)        0.0       0.0       0.0    -DE/DX =    0.0          !
! D13   D(12,1,6,5)      120.1316  116.9853  119.9037 -DE/DX =    0.0          !
! D14   D(12,1,6,10)       0.0       0.0       0.0    -DE/DX =    0.0          !
! D15   D(12,1,6,11)    -115.5087 -121.4353 -120.7965 -DE/DX =    0.0          !
! D16   D(1,2,3,4)       -64.8183 -114.6503  -95.8625 -DE/DX =    0.0          !
! D17   D(1,2,3,13)     -175.9761  127.1791 -179.126  -DE/DX =    0.0          !
! D18   D(1,2,3,14)       34.3014    4.8714    1.1023 -DE/DX =    0.0          !
! D19   D(8,2,3,4)        93.8867   64.2825   83.0289 -DE/DX =    0.0          !
! D20   D(8,2,3,13)      -17.2712  -53.8882   -0.2346 -DE/DX =    0.0          !
! D21   D(8,2,3,14)     -166.9936 -176.1959  179.9937 -DE/DX =    0.0          !
! D22   D(2,3,4,5)         0.0       0.0       0.0    -DE/DX =    0.0          !
! D23   D(2,3,4,15)      120.1451  119.9037  116.9853 -DE/DX =    0.0          !
! D24   D(2,3,4,16)     -124.3478 -119.2998 -121.5795 -DE/DX =    0.0          !
! D25   D(13,3,4,5)      124.3478  119.2998  121.5795 -DE/DX =    0.0          !
! D26   D(13,3,4,15)    -115.5071 -120.7965 -121.4353 -DE/DX =    0.0          !
! D27   D(13,3,4,16)       0.0       0.0       0.0    -DE/DX =    0.0          !
! D28   D(14,3,4,5)     -120.1451 -119.9037 -116.9853 -DE/DX =    0.0          !
! D29   D(14,3,4,15)       0.0       0.0       0.0    -DE/DX =    0.0          !
! D30   D(14,3,4,16)     115.5071  120.7965  121.4353 -DE/DX =    0.0          !
! D31   D(3,4,5,6)        64.8183  114.6503   95.8625 -DE/DX =    0.0          !
! D32   D(3,4,5,9)       -93.8867  -64.2825  -83.0289 -DE/DX =    0.0          !
! D33   D(15,4,5,6)      -34.3014   -4.8714   -1.1023 -DE/DX =    0.0          !
! D34   D(15,4,5,9)      166.9936  176.1959 -179.9937 -DE/DX =    0.0          !
! D35   D(16,4,5,6)      175.9761 -127.1791  179.126  -DE/DX =    0.0          !
! D36   D(16,4,5,9)       17.2712   53.8882    0.2346 -DE/DX =    0.0          !
! D37   D(4,5,6,1)       -64.8318  -95.8625 -114.6503 -DE/DX =    0.0          !
! D38   D(4,5,6,10)       34.3366    1.1023    4.8714 -DE/DX =    0.0001       !
! D39   D(4,5,6,11)     -176.0402 -179.126   127.1791 -DE/DX =    0.0          !
! D40   D(9,5,6,1)        93.873    83.0289   64.2825 -DE/DX =    0.0          !
! D41   D(9,5,6,10)     -166.9586  179.9937 -176.1959 -DE/DX =    0.0          !
! D42   D(9,5,6,11)      -17.3354   -0.2346  -53.8882 -DE/DX =   -0.0001       !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


The point group of the optimised structure is C2v, confirming the structure is correct.


6. Vibrational frequencies


As the above table is shown, there is only one imaginary frequency that has a magnitude of 839.62 cm-1. The corresponding vibrational mode is shown below. Although the geometry is different, the boat structure has a similar vibrational motion as the chair structure obtained earlier, that is, two nearby terminal C atoms of the two allyl fragments approach each other in a sychronised motion and facilitates a bond formation, while the other pair of terminal C atoms move away from each other in a sychronised motion and represents a bond breaking. Again, the bond forming and breaking happens at the same time.



7. Thermochemistry

Sum of electronic and zero-point Energies=           -231.450934
Sum of electronic and thermal Energies=              -231.445305
Sum of electronic and thermal Enthalpies=            -231.444361
Sum of electronic and thermal Free Energies=         -231.479780


8. Key information

Transition state type Job type Method Basis set Memory limit Energy Point group
Boat Optimisation to a TS (QST2) HF 3-21G Default -231.60280218 a.u. C2v


(f) IRC analysis of optimised chair and boat transition states

IRC analysis of optimised chair transition state

1. Calculating minimum energy path from chair transition state


As the reaction coordinate is symmetrical in the cope rearrangement, "forward only" is chosen for this IRC calculation. There are 44 intermediate geometries obtianed, which are connected together to show the geometric change following the calculated minimum energy path from the boat transition structure to either reactant or product.


2. File link
The IRC analysed file is linked to here.


3. Structure of the last point of the IRC calculation

test molecule


4. General information of the last point of the IRC calculation


The gradient is less than 0.001, which means the optimisation is complete.


5. Symmetry information of the last point of the IRC calculation


6. Key information of the IRC calculation

Transition state type Job type Method Basis set Memory limit Energy of the last point Point group of the last point
Chair IRC, forward only, calculate always, compute 50 points HF 3-21G Default -231.69157863 a.u. C2


7. IRC plot of the IRC calculation


As the IRC plot is shown above, the energy minimum is not reached in this calculation because the RMS gradient does not reach 0 in the end. Now there are three options can be used to give a more accurate and reliable result: (1) run normal minimisation on the last point of this IRC calculation, (2) redo the IRC calculation to compute a larger number of points until the minimum is reached, (3) redo the IRC calculation to compute the force constants at every step. As the RMS gradient is very close to 0 already, I decided to try the first approach in the following.


(1) Normal minimisation

1. Optimising the last point of the IRC calculation using HF/3-21G

test molecule


The structure looks almost the same as the one before optimisation.


2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete. And the energy is the minimum I found, which is only slightly lower than that before optimisation.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000010     0.000450     YES
RMS     Force            0.000003     0.000300     YES
Maximum Displacement     0.000297     0.001800     YES
RMS     Displacement     0.000090     0.001200     YES
Predicted change in Energy=-2.412823D-09
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.5083         -DE/DX =    0.0                 !
! R2    R(1,3)                  1.087          -DE/DX =    0.0                 !
! R3    R(1,4)                  1.0849         -DE/DX =    0.0                 !
! R4    R(1,9)                  1.5508         -DE/DX =    0.0                 !
! R5    R(2,5)                  1.0768         -DE/DX =    0.0                 !
! R6    R(2,6)                  1.3157         -DE/DX =    0.0                 !
! R7    R(6,7)                  1.0746         -DE/DX =    0.0                 !
! R8    R(6,8)                  1.0733         -DE/DX =    0.0                 !
! R9    R(9,10)                 1.5083         -DE/DX =    0.0                 !
! R10   R(9,11)                 1.087          -DE/DX =    0.0                 !
! R11   R(9,12)                 1.0849         -DE/DX =    0.0                 !
! R12   R(10,13)                1.0768         -DE/DX =    0.0                 !
! R13   R(10,14)                1.3157         -DE/DX =    0.0                 !
! R14   R(14,15)                1.0746         -DE/DX =    0.0                 !
! R15   R(14,16)                1.0733         -DE/DX =    0.0                 !
! A1    A(2,1,3)              109.2943         -DE/DX =    0.0                 !
! A2    A(2,1,4)              109.9836         -DE/DX =    0.0                 !
! A3    A(2,1,9)              112.0405         -DE/DX =    0.0                 !
! A4    A(3,1,4)              107.4615         -DE/DX =    0.0                 !
! A5    A(3,1,9)              108.389          -DE/DX =    0.0                 !
! A6    A(4,1,9)              109.5498         -DE/DX =    0.0                 !
! A7    A(1,2,5)              115.3201         -DE/DX =    0.0                 !
! A8    A(1,2,6)              124.9751         -DE/DX =    0.0                 !
! A9    A(5,2,6)              119.7048         -DE/DX =    0.0                 !
! A10   A(2,6,7)              121.8623         -DE/DX =    0.0                 !
! A11   A(2,6,8)              121.8382         -DE/DX =    0.0                 !
! A12   A(7,6,8)              116.2993         -DE/DX =    0.0                 !
! A13   A(1,9,10)             112.0405         -DE/DX =    0.0                 !
! A14   A(1,9,11)             108.389          -DE/DX =    0.0                 !
! A15   A(1,9,12)             109.5498         -DE/DX =    0.0                 !
! A16   A(10,9,11)            109.2943         -DE/DX =    0.0                 !
! A17   A(10,9,12)            109.9836         -DE/DX =    0.0                 !
! A18   A(11,9,12)            107.4615         -DE/DX =    0.0                 !
! A19   A(9,10,13)            115.3201         -DE/DX =    0.0                 !
! A20   A(9,10,14)            124.9751         -DE/DX =    0.0                 !
! A21   A(13,10,14)           119.7048         -DE/DX =    0.0                 !
! A22   A(10,14,15)           121.8623         -DE/DX =    0.0                 !
! A23   A(10,14,16)           121.8382         -DE/DX =    0.0                 !
! A24   A(15,14,16)           116.2993         -DE/DX =    0.0                 !
! D1    D(3,1,2,5)             64.0448         -DE/DX =    0.0                 !
! D2    D(3,1,2,6)           -115.9105         -DE/DX =    0.0                 !
! D3    D(4,1,2,5)           -178.2065         -DE/DX =    0.0                 !
! D4    D(4,1,2,6)              1.8382         -DE/DX =    0.0                 !
! D5    D(9,1,2,5)            -56.1091         -DE/DX =    0.0                 !
! D6    D(9,1,2,6)            123.9356         -DE/DX =    0.0                 !
! D7    D(2,1,9,10)           -64.1694         -DE/DX =    0.0                 !
! D8    D(2,1,9,11)           175.1506         -DE/DX =    0.0                 !
! D9    D(2,1,9,12)            58.1754         -DE/DX =    0.0                 !
! D10   D(3,1,9,10)           175.1506         -DE/DX =    0.0                 !
! D11   D(3,1,9,11)            54.4706         -DE/DX =    0.0                 !
! D12   D(3,1,9,12)           -62.5047         -DE/DX =    0.0                 !
! D13   D(4,1,9,10)            58.1754         -DE/DX =    0.0                 !
! D14   D(4,1,9,11)           -62.5047         -DE/DX =    0.0                 !
! D15   D(4,1,9,12)          -179.4799         -DE/DX =    0.0                 !
! D16   D(1,2,6,7)             -0.3267         -DE/DX =    0.0                 !
! D17   D(1,2,6,8)            179.8392         -DE/DX =    0.0                 !
! D18   D(5,2,6,7)            179.7198         -DE/DX =    0.0                 !
! D19   D(5,2,6,8)             -0.1143         -DE/DX =    0.0                 !
! D20   D(1,9,10,13)          -56.1091         -DE/DX =    0.0                 !
! D21   D(1,9,10,14)          123.9356         -DE/DX =    0.0                 !
! D22   D(11,9,10,13)          64.0448         -DE/DX =    0.0                 !
! D23   D(11,9,10,14)        -115.9105         -DE/DX =    0.0                 !
! D24   D(12,9,10,13)        -178.2065         -DE/DX =    0.0                 !
! D25   D(12,9,10,14)           1.8382         -DE/DX =    0.0                 !
! D26   D(9,10,14,15)          -0.3267         -DE/DX =    0.0                 !
! D27   D(9,10,14,16)         179.8392         -DE/DX =    0.0                 !
! D28   D(13,10,14,15)        179.7198         -DE/DX =    0.0                 !
! D29   D(13,10,14,16)         -0.1143         -DE/DX =    0.0                 !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


6. Key information

Transition state type Job type Method Basis set Memory limit Energy Point group
Chair Optimisation to a minimum HF 3-21G Default -231.69166702 a.u. C2


IRC analysis of optimised boat transition state

1. Calculating minimum energy path from boat transition state


As the reaction coordinate is symmetrical in the cope rearrangement, "forward only" is chosen for this IRC calculation. There are 45 intermediate geometries obtianed, which are connected together to show the geometric change following the calculated minimum energy path from the boat transition structure to either reactant or product.


2. File link
The IRC analysed file is linked to here.


3. Structure of the last point of the IRC calculation

test molecule


4. General information of the last point of the IRC calculation


The gradient is less than 0.001, which means the optimisation is complete.


5. Symmetry information of the last point of the IRC calculation


6. Key information of the IRC calculation

Transition state type Job type Method Basis set Memory limit Energy of the last point Point group of the last point
Boat IRC, forward only, calculate always, compute 50 points HF 3-21G Default -231.68298284 a.u. Cs


7. IRC plot of the IRC calculation


As the IRC plot is shown above, the RMS gradient is very close to 0 but not exactly equal to 0, so I decided to run a normal minimisation for the last point of this IRC calculation in order to obtain a more accurate minimum.


(1) Normal minimisation

1. Optimising last point of the IRC calculation using HF/3-21G

test molecule


The structure looks almost the same as the one before optimisation.


2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete. And the energy is the minimum I found, which is just slightly lower than that before optimisation.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000019     0.000450     YES
RMS     Force            0.000003     0.000300     YES
Maximum Displacement     0.000234     0.001800     YES
RMS     Displacement     0.000048     0.001200     YES
Predicted change in Energy=-4.234929D-09
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.5104         -DE/DX =    0.0                 !
! R2    R(1,6)                  1.5764         -DE/DX =    0.0                 !
! R3    R(1,7)                  1.0854         -DE/DX =    0.0                 !
! R4    R(1,12)                 1.0832         -DE/DX =    0.0                 !
! R5    R(2,3)                  1.3158         -DE/DX =    0.0                 !
! R6    R(2,8)                  1.0756         -DE/DX =    0.0                 !
! R7    R(3,4)                  4.3471         -DE/DX =    0.0                 !
! R8    R(3,13)                 1.0733         -DE/DX =    0.0                 !
! R9    R(3,14)                 1.0745         -DE/DX =    0.0                 !
! R10   R(4,5)                  1.3158         -DE/DX =    0.0                 !
! R11   R(4,15)                 1.0745         -DE/DX =    0.0                 !
! R12   R(4,16)                 1.0733         -DE/DX =    0.0                 !
! R13   R(5,6)                  1.5104         -DE/DX =    0.0                 !
! R14   R(5,9)                  1.0756         -DE/DX =    0.0                 !
! R15   R(6,10)                 1.0832         -DE/DX =    0.0                 !
! R16   R(6,11)                 1.0854         -DE/DX =    0.0                 !
! A1    A(2,1,6)              114.7587         -DE/DX =    0.0                 !
! A2    A(2,1,7)              108.6492         -DE/DX =    0.0                 !
! A3    A(2,1,12)             108.7769         -DE/DX =    0.0                 !
! A4    A(6,1,7)              108.6886         -DE/DX =    0.0                 !
! A5    A(6,1,12)             108.6894         -DE/DX =    0.0                 !
! A6    A(7,1,12)             107.0064         -DE/DX =    0.0                 !
! A7    A(1,2,3)              124.4302         -DE/DX =    0.0                 !
! A8    A(1,2,8)              116.122          -DE/DX =    0.0                 !
! A9    A(3,2,8)              119.4388         -DE/DX =    0.0                 !
! A10   A(2,3,4)               55.1012         -DE/DX =    0.0                 !
! A11   A(2,3,13)             121.8398         -DE/DX =    0.0                 !
! A12   A(2,3,14)             121.8492         -DE/DX =    0.0                 !
! A13   A(4,3,13)             114.2083         -DE/DX =    0.0                 !
! A14   A(4,3,14)             101.0171         -DE/DX =    0.0                 !
! A15   A(13,3,14)            116.3106         -DE/DX =    0.0                 !
! A16   A(3,4,5)               55.1012         -DE/DX =    0.0                 !
! A17   A(3,4,15)             101.0171         -DE/DX =    0.0                 !
! A18   A(3,4,16)             114.2083         -DE/DX =    0.0                 !
! A19   A(5,4,15)             121.8492         -DE/DX =    0.0                 !
! A20   A(5,4,16)             121.8398         -DE/DX =    0.0                 !
! A21   A(15,4,16)            116.3106         -DE/DX =    0.0                 !
! A22   A(4,5,6)              124.4302         -DE/DX =    0.0                 !
! A23   A(4,5,9)              119.4388         -DE/DX =    0.0                 !
! A24   A(6,5,9)              116.122          -DE/DX =    0.0                 !
! A25   A(1,6,5)              114.7587         -DE/DX =    0.0                 !
! A26   A(1,6,10)             108.6894         -DE/DX =    0.0                 !
! A27   A(1,6,11)             108.6886         -DE/DX =    0.0                 !
! A28   A(5,6,10)             108.7769         -DE/DX =    0.0                 !
! A29   A(5,6,11)             108.6492         -DE/DX =    0.0                 !
! A30   A(10,6,11)            107.0064         -DE/DX =    0.0                 !
! D1    D(6,1,2,3)            116.5974         -DE/DX =    0.0                 !
! D2    D(6,1,2,8)            -64.5            -DE/DX =    0.0                 !
! D3    D(7,1,2,3)           -121.5281         -DE/DX =    0.0                 !
! D4    D(7,1,2,8)             57.3745         -DE/DX =    0.0                 !
! D5    D(12,1,2,3)            -5.3745         -DE/DX =    0.0                 !
! D6    D(12,1,2,8)           173.5281         -DE/DX =    0.0                 !
! D7    D(2,1,6,5)              0.0            -DE/DX =    0.0                 !
! D8    D(2,1,6,10)          -122.0194         -DE/DX =    0.0                 !
! D9    D(2,1,6,11)           121.8531         -DE/DX =    0.0                 !
! D10   D(7,1,6,5)           -121.8531         -DE/DX =    0.0                 !
! D11   D(7,1,6,10)           116.1275         -DE/DX =    0.0                 !
! D12   D(7,1,6,11)             0.0            -DE/DX =    0.0                 !
! D13   D(12,1,6,5)           122.0194         -DE/DX =    0.0                 !
! D14   D(12,1,6,10)            0.0            -DE/DX =    0.0                 !
! D15   D(12,1,6,11)         -116.1275         -DE/DX =    0.0                 !
! D16   D(1,2,3,4)            -81.9003         -DE/DX =    0.0                 !
! D17   D(1,2,3,13)           179.1634         -DE/DX =    0.0                 !
! D18   D(1,2,3,14)            -1.0516         -DE/DX =    0.0                 !
! D19   D(8,2,3,4)             99.2311         -DE/DX =    0.0                 !
! D20   D(8,2,3,13)             0.2948         -DE/DX =    0.0                 !
! D21   D(8,2,3,14)          -179.9202         -DE/DX =    0.0                 !
! D22   D(2,3,4,5)              0.0            -DE/DX =    0.0                 !
! D23   D(2,3,4,15)           121.3093         -DE/DX =    0.0                 !
! D24   D(2,3,4,16)          -113.0549         -DE/DX =    0.0                 !
! D25   D(13,3,4,5)           113.0549         -DE/DX =    0.0                 !
! D26   D(13,3,4,15)         -125.6357         -DE/DX =    0.0                 !
! D27   D(13,3,4,16)            0.0            -DE/DX =    0.0                 !
! D28   D(14,3,4,5)          -121.3093         -DE/DX =    0.0                 !
! D29   D(14,3,4,15)            0.0            -DE/DX =    0.0                 !
! D30   D(14,3,4,16)          125.6357         -DE/DX =    0.0                 !
! D31   D(3,4,5,6)             81.9003         -DE/DX =    0.0                 !
! D32   D(3,4,5,9)            -99.2311         -DE/DX =    0.0                 !
! D33   D(15,4,5,6)             1.0516         -DE/DX =    0.0                 !
! D34   D(15,4,5,9)           179.9202         -DE/DX =    0.0                 !
! D35   D(16,4,5,6)          -179.1634         -DE/DX =    0.0                 !
! D36   D(16,4,5,9)            -0.2948         -DE/DX =    0.0                 !
! D37   D(4,5,6,1)           -116.5974         -DE/DX =    0.0                 !
! D38   D(4,5,6,10)             5.3745         -DE/DX =    0.0                 !
! D39   D(4,5,6,11)           121.5281         -DE/DX =    0.0                 !
! D40   D(9,5,6,1)             64.5            -DE/DX =    0.0                 !
! D41   D(9,5,6,10)          -173.5281         -DE/DX =    0.0                 !
! D42   D(9,5,6,11)           -57.3745         -DE/DX =    0.0                 !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


6. Key information

Transition state type Job type Method Basis set Memory limit Energy Point group
Boat Optimisation to a minimum HF 3-21G Default -231.68302549 a.u. Cs


(g) Reoptimisation of chair and boat transition states using B3LYP/6-31G(d)

Reoptimisation of chair transition state

1. Optimising chair transition state using B3LYP/6-31G(d)

test molecule


2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000027     0.000450     YES
RMS     Force            0.000005     0.000300     YES
Maximum Displacement     0.000107     0.001800     YES
RMS     Displacement     0.000035     0.001200     YES
Predicted change in Energy=-5.303195D-09
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.4075         -DE/DX =    0.0                 !
! R2    R(1,3)                  1.0899         -DE/DX =    0.0                 !
! R3    R(1,4)                  1.0886         -DE/DX =    0.0                 !
! R4    R(1,9)                  1.9675         -DE/DX =    0.0                 !
! R5    R(1,11)                 2.4452         -DE/DX =    0.0                 !
! R6    R(1,12)                 2.3736         -DE/DX =    0.0                 !
! R7    R(2,5)                  1.0905         -DE/DX =    0.0                 !
! R8    R(2,6)                  1.4075         -DE/DX =    0.0                 !
! R9    R(3,9)                  2.4452         -DE/DX =    0.0                 !
! R10   R(4,9)                  2.3736         -DE/DX =    0.0                 !
! R11   R(6,7)                  1.0886         -DE/DX =    0.0                 !
! R12   R(6,8)                  1.0899         -DE/DX =    0.0                 !
! R13   R(6,14)                 1.9675         -DE/DX =    0.0                 !
! R14   R(6,15)                 2.3736         -DE/DX =    0.0                 !
! R15   R(6,16)                 2.4452         -DE/DX =    0.0                 !
! R16   R(7,14)                 2.3736         -DE/DX =    0.0                 !
! R17   R(8,14)                 2.4452         -DE/DX =    0.0                 !
! R18   R(9,10)                 1.4075         -DE/DX =    0.0                 !
! R19   R(9,11)                 1.0899         -DE/DX =    0.0                 !
! R20   R(9,12)                 1.0886         -DE/DX =    0.0                 !
! R21   R(10,13)                1.0905         -DE/DX =    0.0                 !
! R22   R(10,14)                1.4075         -DE/DX =    0.0                 !
! R23   R(14,15)                1.0886         -DE/DX =    0.0                 !
! R24   R(14,16)                1.0899         -DE/DX =    0.0                 !
! A1    A(2,1,3)              118.2534         -DE/DX =    0.0                 !
! A2    A(2,1,4)              117.9645         -DE/DX =    0.0                 !
! A3    A(2,1,9)              103.6352         -DE/DX =    0.0                 !
! A4    A(2,1,11)             129.4131         -DE/DX =    0.0                 !
! A5    A(2,1,12)              92.2714         -DE/DX =    0.0                 !
! A6    A(3,1,4)              112.4945         -DE/DX =    0.0                 !
! A7    A(3,1,11)              88.5074         -DE/DX =    0.0                 !
! A8    A(3,1,12)              86.7983         -DE/DX =    0.0                 !
! A9    A(4,1,11)              83.1889         -DE/DX =    0.0                 !
! A10   A(4,1,12)             124.4235         -DE/DX =    0.0                 !
! A11   A(11,1,12)             44.126          -DE/DX =    0.0                 !
! A12   A(1,2,5)              117.6354         -DE/DX =    0.0                 !
! A13   A(1,2,6)              119.951          -DE/DX =    0.0                 !
! A14   A(5,2,6)              117.6354         -DE/DX =    0.0                 !
! A15   A(2,6,7)              117.9645         -DE/DX =    0.0                 !
! A16   A(2,6,8)              118.2534         -DE/DX =    0.0                 !
! A17   A(2,6,14)             103.6353         -DE/DX =    0.0                 !
! A18   A(2,6,15)              92.2714         -DE/DX =    0.0                 !
! A19   A(2,6,16)             129.4132         -DE/DX =    0.0                 !
! A20   A(7,6,8)              112.4944         -DE/DX =    0.0                 !
! A21   A(7,6,15)             124.4236         -DE/DX =    0.0                 !
! A22   A(7,6,16)              83.189          -DE/DX =    0.0                 !
! A23   A(8,6,15)              86.7983         -DE/DX =    0.0                 !
! A24   A(8,6,16)              88.5075         -DE/DX =    0.0                 !
! A25   A(15,6,16)             44.126          -DE/DX =    0.0                 !
! A26   A(1,9,10)             103.6352         -DE/DX =    0.0                 !
! A27   A(3,9,4)               44.126          -DE/DX =    0.0                 !
! A28   A(3,9,10)             129.4132         -DE/DX =    0.0                 !
! A29   A(3,9,11)              88.5075         -DE/DX =    0.0                 !
! A30   A(3,9,12)              83.1889         -DE/DX =    0.0                 !
! A31   A(4,9,10)              92.2714         -DE/DX =    0.0                 !
! A32   A(4,9,11)              86.7983         -DE/DX =    0.0                 !
! A33   A(4,9,12)             124.4236         -DE/DX =    0.0                 !
! A34   A(10,9,11)            118.2534         -DE/DX =    0.0                 !
! A35   A(10,9,12)            117.9645         -DE/DX =    0.0                 !
! A36   A(11,9,12)            112.4945         -DE/DX =    0.0                 !
! A37   A(9,10,13)            117.6354         -DE/DX =    0.0                 !
! A38   A(9,10,14)            119.951          -DE/DX =    0.0                 !
! A39   A(13,10,14)           117.6354         -DE/DX =    0.0                 !
! A40   A(6,14,10)            103.6352         -DE/DX =    0.0                 !
! A41   A(7,14,8)              44.126          -DE/DX =    0.0                 !
! A42   A(7,14,10)             92.2714         -DE/DX =    0.0                 !
! A43   A(7,14,15)            124.4236         -DE/DX =    0.0                 !
! A44   A(7,14,16)             86.7983         -DE/DX =    0.0                 !
! A45   A(8,14,10)            129.4132         -DE/DX =    0.0                 !
! A46   A(8,14,15)             83.1889         -DE/DX =    0.0                 !
! A47   A(8,14,16)             88.5074         -DE/DX =    0.0                 !
! A48   A(10,14,15)           117.9645         -DE/DX =    0.0                 !
! A49   A(10,14,16)           118.2534         -DE/DX =    0.0                 !
! A50   A(15,14,16)           112.4944         -DE/DX =    0.0                 !
! D1    D(3,1,2,5)             22.6226         -DE/DX =    0.0                 !
! D2    D(3,1,2,6)            177.5758         -DE/DX =    0.0                 !
! D3    D(4,1,2,5)            163.6158         -DE/DX =    0.0                 !
! D4    D(4,1,2,6)            -41.431          -DE/DX =    0.0                 !
! D5    D(9,1,2,5)            -89.7714         -DE/DX =    0.0                 !
! D6    D(9,1,2,6)             65.1818         -DE/DX =    0.0                 !
! D7    D(11,1,2,5)           -91.1655         -DE/DX =    0.0                 !
! D8    D(11,1,2,6)            63.7877         -DE/DX =    0.0                 !
! D9    D(12,1,2,5)           -64.9622         -DE/DX =    0.0                 !
! D10   D(12,1,2,6)            89.991          -DE/DX =    0.0                 !
! D11   D(2,1,9,10)           -54.0215         -DE/DX =    0.0                 !
! D12   D(1,2,6,7)             41.4311         -DE/DX =    0.0                 !
! D13   D(1,2,6,8)           -177.5759         -DE/DX =    0.0                 !
! D14   D(1,2,6,14)           -65.1818         -DE/DX =    0.0                 !
! D15   D(1,2,6,15)           -89.991          -DE/DX =    0.0                 !
! D16   D(1,2,6,16)           -63.7878         -DE/DX =    0.0                 !
! D17   D(5,2,6,7)           -163.6157         -DE/DX =    0.0                 !
! D18   D(5,2,6,8)            -22.6227         -DE/DX =    0.0                 !
! D19   D(5,2,6,14)            89.7714         -DE/DX =    0.0                 !
! D20   D(5,2,6,15)            64.9622         -DE/DX =    0.0                 !
! D21   D(5,2,6,16)            91.1655         -DE/DX =    0.0                 !
! D22   D(2,6,14,10)           54.0216         -DE/DX =    0.0                 !
! D23   D(1,9,10,13)          -89.7714         -DE/DX =    0.0                 !
! D24   D(1,9,10,14)           65.1818         -DE/DX =    0.0                 !
! D25   D(3,9,10,13)          -91.1655         -DE/DX =    0.0                 !
! D26   D(3,9,10,14)           63.7877         -DE/DX =    0.0                 !
! D27   D(4,9,10,13)          -64.9622         -DE/DX =    0.0                 !
! D28   D(4,9,10,14)           89.991          -DE/DX =    0.0                 !
! D29   D(11,9,10,13)          22.6227         -DE/DX =    0.0                 !
! D30   D(11,9,10,14)         177.5759         -DE/DX =    0.0                 !
! D31   D(12,9,10,13)         163.6158         -DE/DX =    0.0                 !
! D32   D(12,9,10,14)         -41.431          -DE/DX =    0.0                 !
! D33   D(9,10,14,6)          -65.1818         -DE/DX =    0.0                 !
! D34   D(9,10,14,7)          -89.991          -DE/DX =    0.0                 !
! D35   D(9,10,14,8)          -63.7877         -DE/DX =    0.0                 !
! D36   D(9,10,14,15)          41.431          -DE/DX =    0.0                 !
! D37   D(9,10,14,16)        -177.5758         -DE/DX =    0.0                 !
! D38   D(13,10,14,6)          89.7714         -DE/DX =    0.0                 !
! D39   D(13,10,14,7)          64.9622         -DE/DX =    0.0                 !
! D40   D(13,10,14,8)          91.1655         -DE/DX =    0.0                 !
! D41   D(13,10,14,15)       -163.6158         -DE/DX =    0.0                 !
! D42   D(13,10,14,16)        -22.6226         -DE/DX =    0.0                 !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


The point group of the optimised structure is C2h, confirming the structure is correct.


6. Vibrational frequencies


As the above table is shown, there is only one imaginary frequency that has a magnitude of 565.53 cm-1 which is lower than that of the HF/3-21G optimised structure (i.e. 818.02 cm-1). The corresponding vibrational mode is shown below, and the motion is similar to that of the HF/3-21G optimised structure but slower.



7. Thermochemistry

Sum of electronic and zero-point Energies=           -234.414929
Sum of electronic and thermal Energies=              -234.409008
Sum of electronic and thermal Enthalpies=            -234.408064
Sum of electronic and thermal Free Energies=         -234.443814


8. Key information

Transition state type Job type Additional keywords Method Basis set Memory limit Energy Point group
Chair Optimisation to a TS (Berny), calculate the force constants once Opt=NoEigen B3LYP 6-31G(d) Default -234.55698303 a.u. C2h


Reoptimisation of boat transition state

1. Optimising boat transition state using B3LYP/6-31G(d)

test molecule


2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000129     0.000450     YES
RMS     Force            0.000025     0.000300     YES
Maximum Displacement     0.001795     0.001800     YES
RMS     Displacement     0.000585     0.001200     YES
Predicted change in Energy=-1.407564D-07
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.3931         -DE/DX =    0.0                 !
! R2    R(1,6)                  2.2073         -DE/DX =    0.0001              !
! R3    R(1,7)                  1.087          -DE/DX =    0.0                 !
! R4    R(1,12)                 1.0868         -DE/DX =    0.0                 !
! R5    R(2,3)                  1.3934         -DE/DX =    0.0                 !
! R6    R(2,8)                  1.0911         -DE/DX =    0.0                 !
! R7    R(3,4)                  2.2053         -DE/DX =    0.0                 !
! R8    R(3,13)                 1.087          -DE/DX =    0.0                 !
! R9    R(3,14)                 1.0868         -DE/DX =    0.0                 !
! R10   R(4,5)                  1.3934         -DE/DX =    0.0                 !
! R11   R(4,15)                 1.0868         -DE/DX =    0.0                 !
! R12   R(4,16)                 1.087          -DE/DX =    0.0                 !
! R13   R(5,6)                  1.3931         -DE/DX =    0.0                 !
! R14   R(5,9)                  1.0911         -DE/DX =    0.0                 !
! R15   R(6,10)                 1.0868         -DE/DX =    0.0                 !
! R16   R(6,11)                 1.087          -DE/DX =    0.0                 !
! A1    A(2,1,6)              103.479          -DE/DX =    0.0                 !
! A2    A(2,1,7)              119.7469         -DE/DX =    0.0                 !
! A3    A(2,1,12)             118.9444         -DE/DX =    0.0                 !
! A4    A(6,1,7)              101.9234         -DE/DX =    0.0                 !
! A5    A(6,1,12)              90.4694         -DE/DX =    0.0                 !
! A6    A(7,1,12)             114.4414         -DE/DX =    0.0                 !
! A7    A(1,2,3)              122.2408         -DE/DX =    0.0001              !
! A8    A(1,2,8)              117.1548         -DE/DX =    0.0                 !
! A9    A(3,2,8)              117.1587         -DE/DX =    0.0                 !
! A10   A(2,3,4)              103.5173         -DE/DX =    0.0                 !
! A11   A(2,3,13)             119.7332         -DE/DX =    0.0                 !
! A12   A(2,3,14)             118.9246         -DE/DX =    0.0                 !
! A13   A(4,3,13)             101.9344         -DE/DX =    0.0                 !
! A14   A(4,3,14)              90.4988         -DE/DX =    0.0                 !
! A15   A(13,3,14)            114.4342         -DE/DX =    0.0                 !
! A16   A(3,4,5)              103.5173         -DE/DX =    0.0                 !
! A17   A(3,4,15)              90.4988         -DE/DX =    0.0                 !
! A18   A(3,4,16)             101.9344         -DE/DX =    0.0                 !
! A19   A(5,4,15)             118.9246         -DE/DX =    0.0                 !
! A20   A(5,4,16)             119.7332         -DE/DX =    0.0                 !
! A21   A(15,4,16)            114.4342         -DE/DX =    0.0                 !
! A22   A(4,5,6)              122.2408         -DE/DX =    0.0001              !
! A23   A(4,5,9)              117.1587         -DE/DX =    0.0                 !
! A24   A(6,5,9)              117.1548         -DE/DX =    0.0                 !
! A25   A(1,6,5)              103.479          -DE/DX =    0.0                 !
! A26   A(1,6,10)              90.4694         -DE/DX =    0.0                 !
! A27   A(1,6,11)             101.9234         -DE/DX =    0.0                 !
! A28   A(5,6,10)             118.9444         -DE/DX =    0.0                 !
! A29   A(5,6,11)             119.7469         -DE/DX =    0.0                 !
! A30   A(10,6,11)            114.4414         -DE/DX =    0.0                 !
! D1    D(6,1,2,3)             64.1921         -DE/DX =    0.0                 !
! D2    D(6,1,2,8)            -94.2493         -DE/DX =    0.0                 !
! D3    D(7,1,2,3)            176.6297         -DE/DX =    0.0                 !
! D4    D(7,1,2,8)             18.1883         -DE/DX =    0.0                 !
! D5    D(12,1,2,3)           -33.9823         -DE/DX =    0.0                 !
! D6    D(12,1,2,8)           167.5763         -DE/DX =    0.0                 !
! D7    D(2,1,6,5)              0.0            -DE/DX =    0.0                 !
! D8    D(2,1,6,10)          -119.9768         -DE/DX =    0.0                 !
! D9    D(2,1,6,11)           124.8959         -DE/DX =    0.0                 !
! D10   D(7,1,6,5)           -124.8959         -DE/DX =    0.0                 !
! D11   D(7,1,6,10)           115.1273         -DE/DX =    0.0                 !
! D12   D(7,1,6,11)             0.0            -DE/DX =    0.0                 !
! D13   D(12,1,6,5)           119.9768         -DE/DX =    0.0                 !
! D14   D(12,1,6,10)            0.0            -DE/DX =    0.0                 !
! D15   D(12,1,6,11)         -115.1273         -DE/DX =    0.0                 !
! D16   D(1,2,3,4)            -64.2111         -DE/DX =    0.0                 !
! D17   D(1,2,3,13)          -176.6833         -DE/DX =    0.0                 !
! D18   D(1,2,3,14)            34.0145         -DE/DX =    0.0                 !
! D19   D(8,2,3,4)             94.2295         -DE/DX =    0.0                 !
! D20   D(8,2,3,13)           -18.2427         -DE/DX =    0.0                 !
! D21   D(8,2,3,14)          -167.5449         -DE/DX =    0.0                 !
! D22   D(2,3,4,5)              0.0            -DE/DX =    0.0                 !
! D23   D(2,3,4,15)           119.9702         -DE/DX =    0.0                 !
! D24   D(2,3,4,16)          -124.9018         -DE/DX =    0.0                 !
! D25   D(13,3,4,5)           124.9018         -DE/DX =    0.0                 !
! D26   D(13,3,4,15)         -115.128          -DE/DX =    0.0                 !
! D27   D(13,3,4,16)            0.0            -DE/DX =    0.0                 !
! D28   D(14,3,4,5)          -119.9702         -DE/DX =    0.0                 !
! D29   D(14,3,4,15)            0.0            -DE/DX =    0.0                 !
! D30   D(14,3,4,16)          115.128          -DE/DX =    0.0                 !
! D31   D(3,4,5,6)             64.2111         -DE/DX =    0.0                 !
! D32   D(3,4,5,9)            -94.2295         -DE/DX =    0.0                 !
! D33   D(15,4,5,6)           -34.0145         -DE/DX =    0.0                 !
! D34   D(15,4,5,9)           167.5449         -DE/DX =    0.0                 !
! D35   D(16,4,5,6)           176.6833         -DE/DX =    0.0                 !
! D36   D(16,4,5,9)            18.2427         -DE/DX =    0.0                 !
! D37   D(4,5,6,1)            -64.1921         -DE/DX =    0.0                 !
! D38   D(4,5,6,10)            33.9823         -DE/DX =    0.0                 !
! D39   D(4,5,6,11)          -176.6297         -DE/DX =    0.0                 !
! D40   D(9,5,6,1)             94.2493         -DE/DX =    0.0                 !
! D41   D(9,5,6,10)          -167.5763         -DE/DX =    0.0                 !
! D42   D(9,5,6,11)           -18.1883         -DE/DX =    0.0                 !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


The point group of the optimised structure is C2v, confirming the structure is correct.


6. Vibrational frequencies


As the above table is shown, there is only one imaginary frequency that has a magnitude of 530.43 cm-1 which is lower than that of the HF/3-21G optimised structure (i.e. 839.62 cm-1). The corresponding vibrational mode is shown below, and the motion is similar to that of the HF/3-21G optimised structure but slower.



7. Thermochemistry

Sum of electronic and zero-point Energies=           -234.402336
Sum of electronic and thermal Energies=              -234.396001
Sum of electronic and thermal Enthalpies=            -234.395057
Sum of electronic and thermal Free Energies=         -234.431746


8. Key information

Transition state type Job type Additional keywords Method Basis set Memory limit Energy Point group
Boat Optimisation to a TS (Berny), calculate the force constants once Opt=NoEigen B3LYP 6-31G(d) Default -231.54309298 a.u. C2v


Result and discussion

1. Geometric data comparison
(1) Different optimisations of chair transition state

A GaussView image of a chair transition structure.
Geometric parameter HF/3-21G B3LYP/6-31G(d)
C1=C2 (or C2=C3, C4=C5, C5=C6) bond length 1.38928 Å 1.40749 Å
C3-C4 (or C1=C6) bond length 2.02038 Å 1.96751 Å
C2-C5 bond length 2.87892 Å 2.90970 Å
C2=C3-C4-C5 (or C2-C1-C6=C5) dihedral angle +(or-)54.958o +(or-)54.022o


The difference in geometric data is small for using HF/3-21G and B3LYP/6-31G(d) as the method/basis set for optimisation of chair transition state.


(2) Different optimisations of boat transition state

A GaussView image of a boat transition structure.
Geometric parameter HF/3-21G B3LYP/6-31G(d)
C1=C2 (or C2=C3, C4=C5, C5=C6) bond length 1.38154 Å 1.39307 Å
C3-C4 (or C1=C6) bond length 2.14182 Å 2.20727 Å
C2-C5 bond length 2.77903 Å 2.85669 Å
C2=C3-C4-C5 (or C2-C1-C6=C5) dihedral angle 0o 0o


Similarly, the difference in geometric data is small for using HF/3-21G and B3LYP/6-31G(d) as the method/basis set for optimisation of boat transition state.


2. Thermochemistry data comparison

Literature energy table.


As the energy table shown above, the energy difference between optimisations using HF/3-21G and B3LYP/6-31G(d) is huge, which is approximately 3 a.u. (or 1883 kcal/mol). Moreover, my experimental data is consistent with the data given in literature which is shown on the right.



1 hartree = 627.509 kcal/mol

Literature energy table 2.


My calculated activation energy data also gives a good agreement to the data given in literature which is shown on the right.





The Diels Alder Cycloaddition

Diels Alder Reaction Between Cis-Butadiene and Ethylene

Optimising the Reactants

(a) Optimisation of cis-butadiene

1. Optimising cis butadiene using AM1 method

test molecule


2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000159     0.000450     YES
RMS     Force            0.000051     0.000300     YES
Maximum Displacement     0.000767     0.001800     YES
RMS     Displacement     0.000254     0.001200     YES
Predicted change in Energy=-1.540655D-07
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.335          -DE/DX =    0.0001              !
! R2    R(1,3)                  1.0979         -DE/DX =   -0.0001              !
! R3    R(1,4)                  1.0977         -DE/DX =    0.0                 !
! R4    R(2,5)                  1.1055         -DE/DX =   -0.0002              !
! R5    R(2,6)                  1.4495         -DE/DX =    0.0                 !
! R6    R(6,7)                  1.335          -DE/DX =    0.0001              !
! R7    R(6,8)                  1.1055         -DE/DX =   -0.0002              !
! R8    R(7,9)                  1.0979         -DE/DX =   -0.0001              !
! R9    R(7,10)                 1.0977         -DE/DX =    0.0                 !
! A1    A(2,1,3)              121.928          -DE/DX =    0.0                 !
! A2    A(2,1,4)              123.1583         -DE/DX =    0.0                 !
! A3    A(3,1,4)              114.9137         -DE/DX =    0.0001              !
! A4    A(1,2,5)              119.8212         -DE/DX =    0.0                 !
! A5    A(1,2,6)              125.6618         -DE/DX =    0.0                 !
! A6    A(5,2,6)              114.5169         -DE/DX =    0.0                 !
! A7    A(2,6,7)              125.6618         -DE/DX =    0.0                 !
! A8    A(2,6,8)              114.5169         -DE/DX =    0.0                 !
! A9    A(7,6,8)              119.8212         -DE/DX =    0.0                 !
! A10   A(6,7,9)              121.928          -DE/DX =    0.0                 !
! A11   A(6,7,10)             123.1583         -DE/DX =    0.0                 !
! A12   A(9,7,10)             114.9137         -DE/DX =    0.0001              !
! D1    D(3,1,2,5)              0.0            -DE/DX =    0.0                 !
! D2    D(3,1,2,6)           -180.0003         -DE/DX =    0.0                 !
! D3    D(4,1,2,5)            180.0002         -DE/DX =    0.0                 !
! D4    D(4,1,2,6)              0.0            -DE/DX =    0.0                 !
! D5    D(1,2,6,7)              0.0004         -DE/DX =    0.0                 !
! D6    D(1,2,6,8)           -180.0001         -DE/DX =    0.0                 !
! D7    D(5,2,6,7)           -179.9998         -DE/DX =    0.0                 !
! D8    D(5,2,6,8)             -0.0003         -DE/DX =    0.0                 !
! D9    D(2,6,7,9)           -180.0005         -DE/DX =    0.0                 !
! D10   D(2,6,7,10)            -0.0001         -DE/DX =    0.0                 !
! D11   D(8,6,7,9)              0.0001         -DE/DX =    0.0                 !
! D12   D(8,6,7,10)           180.0005         -DE/DX =    0.0                 !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


6. HOMO/LUMO visialisation


7. Key information

Molecule Job type Method Basis set Memory limit Energy Point group
Cis-butadiene Optimisation to a minimum Semi-empirical molecular orbital, AM1 ZDO Default 0.04879734 a.u. C2v
(b) Optimisation of ethylene

1. Optimising ethylene using AM1 method

test molecule


2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000031     0.000450     YES
RMS     Force            0.000012     0.000300     YES
Maximum Displacement     0.000057     0.001800     YES
RMS     Displacement     0.000037     0.001200     YES
Predicted change in Energy=-2.644693D-09
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.3259         -DE/DX =    0.0                 !
! R2    R(1,3)                  1.0983         -DE/DX =    0.0                 !
! R3    R(1,4)                  1.0983         -DE/DX =    0.0                 !
! R4    R(2,5)                  1.0983         -DE/DX =    0.0                 !
! R5    R(2,6)                  1.0983         -DE/DX =    0.0                 !
! A1    A(2,1,3)              122.7159         -DE/DX =    0.0                 !
! A2    A(2,1,4)              122.718          -DE/DX =    0.0                 !
! A3    A(3,1,4)              114.5661         -DE/DX =    0.0                 !
! A4    A(1,2,5)              122.7159         -DE/DX =    0.0                 !
! A5    A(1,2,6)              122.718          -DE/DX =    0.0                 !
! A6    A(5,2,6)              114.5661         -DE/DX =    0.0                 !
! D1    D(3,1,2,5)            180.0012         -DE/DX =    0.0                 !
! D2    D(3,1,2,6)              0.0016         -DE/DX =    0.0                 !
! D3    D(4,1,2,5)             -0.0002         -DE/DX =    0.0                 !
! D4    D(4,1,2,6)           -179.9998         -DE/DX =    0.0                 !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


6. Key information

Molecule Job type Method Basis set Memory limit Energy Point group
Ethylene Optimisation to a minimum Semi-empirical molecular orbital, AM1 ZDO Default 0.02619024 a.u. D2h


Optimising the Transition Structure

(a) Optimisation of guess transition state

1. Optimising guess transition state using AM1 method


The guess transition state was drawn as above by combining the optimised ethylene and butadiene structures with two partially formed C-C bonds of 2.2 Å bond length and modifying the H-C-H bond angles. The optimised structure is shown below, which has 2.11929 Å bond lengths for the partially formed bonds.


A GaussView image of a optimised transition state using AM1 method.
test molecule


2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000023     0.000450     YES
RMS     Force            0.000004     0.000300     YES
Maximum Displacement     0.000139     0.001800     YES
RMS     Displacement     0.000042     0.001200     YES
Predicted change in Energy=-4.471972D-09
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.3829         -DE/DX =    0.0                 !
! R2    R(1,7)                  2.1193         -DE/DX =    0.0                 !
! R3    R(1,15)                 1.0996         -DE/DX =    0.0                 !
! R4    R(1,16)                 1.1002         -DE/DX =    0.0                 !
! R5    R(2,3)                  2.1192         -DE/DX =    0.0                 !
! R6    R(2,13)                 1.0996         -DE/DX =    0.0                 !
! R7    R(2,14)                 1.1002         -DE/DX =    0.0                 !
! R8    R(3,4)                  1.3818         -DE/DX =    0.0                 !
! R9    R(3,11)                 1.1008         -DE/DX =    0.0                 !
! R10   R(3,12)                 1.0989         -DE/DX =    0.0                 !
! R11   R(4,5)                  1.1018         -DE/DX =    0.0                 !
! R12   R(4,6)                  1.3975         -DE/DX =    0.0                 !
! R13   R(6,7)                  1.3819         -DE/DX =    0.0                 !
! R14   R(6,8)                  1.1018         -DE/DX =    0.0                 !
! R15   R(7,9)                  1.0989         -DE/DX =    0.0                 !
! R16   R(7,10)                 1.1008         -DE/DX =    0.0                 !
! A1    A(2,1,7)              109.9397         -DE/DX =    0.0                 !
! A2    A(2,1,15)             120.0126         -DE/DX =    0.0                 !
! A3    A(2,1,16)             119.9894         -DE/DX =    0.0                 !
! A4    A(7,1,15)              90.8574         -DE/DX =    0.0                 !
! A5    A(7,1,16)              90.1772         -DE/DX =    0.0                 !
! A6    A(15,1,16)            115.2775         -DE/DX =    0.0                 !
! A7    A(1,2,3)              109.941          -DE/DX =    0.0                 !
! A8    A(1,2,13)             120.0109         -DE/DX =    0.0                 !
! A9    A(1,2,14)             119.9897         -DE/DX =    0.0                 !
! A10   A(3,2,13)              90.8556         -DE/DX =    0.0                 !
! A11   A(3,2,14)              90.1806         -DE/DX =    0.0                 !
! A12   A(13,2,14)            115.2778         -DE/DX =    0.0                 !
! A13   A(2,3,4)               99.3392         -DE/DX =    0.0                 !
! A14   A(2,3,11)              88.8726         -DE/DX =    0.0                 !
! A15   A(2,3,12)             101.637          -DE/DX =    0.0                 !
! A16   A(4,3,11)             121.2502         -DE/DX =    0.0                 !
! A17   A(4,3,12)             119.9973         -DE/DX =    0.0                 !
! A18   A(11,3,12)            114.7406         -DE/DX =    0.0                 !
! A19   A(3,4,5)              119.648          -DE/DX =    0.0                 !
! A20   A(3,4,6)              121.1811         -DE/DX =    0.0                 !
! A21   A(5,4,6)              118.3949         -DE/DX =    0.0                 !
! A22   A(4,6,7)              121.185          -DE/DX =    0.0                 !
! A23   A(4,6,8)              118.3929         -DE/DX =    0.0                 !
! A24   A(7,6,8)              119.6444         -DE/DX =    0.0                 !
! A25   A(1,7,6)               99.339          -DE/DX =    0.0                 !
! A26   A(1,7,9)              101.6423         -DE/DX =    0.0                 !
! A27   A(1,7,10)              88.868          -DE/DX =    0.0                 !
! A28   A(6,7,9)              119.9974         -DE/DX =    0.0                 !
! A29   A(6,7,10)             121.247          -DE/DX =    0.0                 !
! A30   A(9,7,10)             114.7435         -DE/DX =    0.0                 !
! D1    D(7,1,2,3)              0.0002         -DE/DX =    0.0                 !
! D2    D(7,1,2,13)           103.1737         -DE/DX =    0.0                 !
! D3    D(7,1,2,14)          -102.3125         -DE/DX =    0.0                 !
! D4    D(15,1,2,3)          -103.1756         -DE/DX =    0.0                 !
! D5    D(15,1,2,13)           -0.002          -DE/DX =    0.0                 !
! D6    D(15,1,2,14)          154.5117         -DE/DX =    0.0                 !
! D7    D(16,1,2,3)           102.3078         -DE/DX =    0.0                 !
! D8    D(16,1,2,13)         -154.5186         -DE/DX =    0.0                 !
! D9    D(16,1,2,14)           -0.0049         -DE/DX =    0.0                 !
! D10   D(2,1,7,6)            -51.8386         -DE/DX =    0.0                 !
! D11   D(2,1,7,9)           -175.2883         -DE/DX =    0.0                 !
! D12   D(2,1,7,10)            69.6647         -DE/DX =    0.0                 !
! D13   D(15,1,7,6)            70.6802         -DE/DX =    0.0                 !
! D14   D(15,1,7,9)           -52.7695         -DE/DX =    0.0                 !
! D15   D(15,1,7,10)         -167.8164         -DE/DX =    0.0                 !
! D16   D(16,1,7,6)          -174.0362         -DE/DX =    0.0                 !
! D17   D(16,1,7,9)            62.5142         -DE/DX =    0.0                 !
! D18   D(16,1,7,10)          -52.5328         -DE/DX =    0.0                 !
! D19   D(1,2,3,4)             51.8417         -DE/DX =    0.0                 !
! D20   D(1,2,3,11)           -69.6659         -DE/DX =    0.0                 !
! D21   D(1,2,3,12)           175.2895         -DE/DX =    0.0                 !
! D22   D(13,2,3,4)           -70.6748         -DE/DX =    0.0                 !
! D23   D(13,2,3,11)          167.8176         -DE/DX =    0.0                 !
! D24   D(13,2,3,12)           52.773          -DE/DX =    0.0                 !
! D25   D(14,2,3,4)           174.0412         -DE/DX =    0.0                 !
! D26   D(14,2,3,11)           52.5336         -DE/DX =    0.0                 !
! D27   D(14,2,3,12)          -62.511          -DE/DX =    0.0                 !
! D28   D(2,3,4,5)            109.9775         -DE/DX =    0.0                 !
! D29   D(2,3,4,6)            -59.7708         -DE/DX =    0.0                 !
! D30   D(11,3,4,5)          -155.6367         -DE/DX =    0.0                 !
! D31   D(11,3,4,6)            34.615          -DE/DX =    0.0                 !
! D32   D(12,3,4,5)             0.6493         -DE/DX =    0.0                 !
! D33   D(12,3,4,6)          -169.099          -DE/DX =    0.0                 !
! D34   D(3,4,6,7)              0.0055         -DE/DX =    0.0                 !
! D35   D(3,4,6,8)            169.8677         -DE/DX =    0.0                 !
! D36   D(5,4,6,7)           -169.8678         -DE/DX =    0.0                 !
! D37   D(5,4,6,8)             -0.0055         -DE/DX =    0.0                 !
! D38   D(4,6,7,1)             59.7623         -DE/DX =    0.0                 !
! D39   D(4,6,7,9)            169.0967         -DE/DX =    0.0                 !
! D40   D(4,6,7,10)           -34.6173         -DE/DX =    0.0                 !
! D41   D(8,6,7,1)           -109.975          -DE/DX =    0.0                 !
! D42   D(8,6,7,9)             -0.6406         -DE/DX =    0.0                 !
! D43   D(8,6,7,10)           155.6454         -DE/DX =    0.0                 !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


6. Vibrational frequencies


As the above table is shown, there is only one imaginary frequency that has a magnitude of 956.25 cm-1. The corresponding vibrational mode is shown below, in which the C atoms of ethylene and the two terminal C atoms of butadiene approach each other in a sychronised motion and facilitates two simultaneous C-C bonds formation. This is exactly what happens in the [4+2] cycloaddtion, that is, two or more C-C bonds form at the same time (i.e. a concerted process) in a 6-membered ring like system.



7. Thermochemistry

Sum of electronic and zero-point Energies=              0.253276
Sum of electronic and thermal Energies=                 0.259453
Sum of electronic and thermal Enthalpies=               0.260397
Sum of electronic and thermal Free Energies=            0.224016


8. HOMO/LUMO visialisation


9. Key information

Subject Job type Additional keywords Method Basis set Memory limit Energy Point group
Transition state Optimisation to a TS (Berny), calculate the force constants once Opt=NoEigen Semi-empirical molecular orbital, AM1 ZDO Default 0.11165465 a.u. Cs


(b) IRC analysis of optimised transition state

1. Calculating minimum energy path from transition state


As the reaction coordinate is not symmetrical in the Diels Alder cycloaddition, "both directions" is chosen for this IRC calculation. There are 87 intermediate geometries, which are connected together to show the geometric change following the calculated minimum energy path from reactant to product via the transition state. The structure of the last point of this IRC calculation is shown below.


test molecule


2. File link
The IRC analysed file is linked to here.


3. IRC plot


As the IRC plot is shown above, the energy minimum is reached in this calculation because the RMS gradient reaches 0 in the end. Therefore no need to conduct further calculation. The general and symmetry information of the last point of this IRC calculation is given in the following.


4. General information


The gradient is less than 0.001, which means the optimisation is complete.


5. Symmetry information


6. Key information

Subject Job type Method Basis set Memory limit Energy Point group
Transition state IRC, both directions, calculate always, compute 100 points Semi-empirical molecular orbital, AM1 ZDO Default -0.01099223 a.u. Cs


(c) Reoptimisation of transition state using B3LYP/6-31G(d)

1. Optimising transition state using B3LYP/6-31G(d)

test molecule


2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000013     0.000450     YES
RMS     Force            0.000002     0.000300     YES
Maximum Displacement     0.000496     0.001800     YES
RMS     Displacement     0.000106     0.001200     YES
Predicted change in Energy=-7.705534D-09
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.386          -DE/DX =    0.0                 !
! R2    R(1,6)                  2.9004         -DE/DX =    0.0                 !
! R3    R(1,7)                  2.2725         -DE/DX =    0.0                 !
! R4    R(1,9)                  2.7536         -DE/DX =    0.0                 !
! R5    R(1,10)                 2.4251         -DE/DX =    0.0                 !
! R6    R(1,15)                 1.0842         -DE/DX =    0.0                 !
! R7    R(1,16)                 1.0863         -DE/DX =    0.0                 !
! R8    R(2,3)                  2.2725         -DE/DX =    0.0                 !
! R9    R(2,4)                  2.9004         -DE/DX =    0.0                 !
! R10   R(2,11)                 2.4251         -DE/DX =    0.0                 !
! R11   R(2,12)                 2.7536         -DE/DX =    0.0                 !
! R12   R(2,13)                 1.0842         -DE/DX =    0.0                 !
! R13   R(2,14)                 1.0863         -DE/DX =    0.0                 !
! R14   R(3,4)                  1.383          -DE/DX =    0.0                 !
! R15   R(3,11)                 1.084          -DE/DX =    0.0                 !
! R16   R(3,12)                 1.0873         -DE/DX =    0.0                 !
! R17   R(3,13)                 2.5399         -DE/DX =    0.0                 !
! R18   R(3,14)                 2.5323         -DE/DX =    0.0                 !
! R19   R(4,5)                  1.0891         -DE/DX =    0.0                 !
! R20   R(4,6)                  1.4072         -DE/DX =    0.0                 !
! R21   R(6,7)                  1.383          -DE/DX =    0.0                 !
! R22   R(6,8)                  1.0891         -DE/DX =    0.0                 !
! R23   R(7,9)                  1.0873         -DE/DX =    0.0                 !
! R24   R(7,10)                 1.084          -DE/DX =    0.0                 !
! R25   R(7,15)                 2.5399         -DE/DX =    0.0                 !
! R26   R(7,16)                 2.5323         -DE/DX =    0.0                 !
! A1    A(2,1,6)               90.2098         -DE/DX =    0.0                 !
! A2    A(2,1,7)              109.1164         -DE/DX =    0.0                 !
! A3    A(2,1,9)              131.4998         -DE/DX =    0.0                 !
! A4    A(2,1,10)              98.9089         -DE/DX =    0.0                 !
! A5    A(2,1,15)             120.0522         -DE/DX =    0.0                 !
! A6    A(2,1,16)             119.9852         -DE/DX =    0.0                 !
! A7    A(6,1,9)               44.4899         -DE/DX =    0.0                 !
! A8    A(6,1,10)              46.5393         -DE/DX =    0.0                 !
! A9    A(6,1,15)              83.3596         -DE/DX =    0.0                 !
! A10   A(6,1,16)             118.2474         -DE/DX =    0.0                 !
! A11   A(9,1,10)              40.6754         -DE/DX =    0.0                 !
! A12   A(9,1,15)              77.8409         -DE/DX =    0.0                 !
! A13   A(9,1,16)              80.5628         -DE/DX =    0.0                 !
! A14   A(10,1,15)            116.9474         -DE/DX =    0.0                 !
! A15   A(10,1,16)             74.6439         -DE/DX =    0.0                 !
! A16   A(15,1,16)            115.1638         -DE/DX =    0.0                 !
! A17   A(1,2,3)              109.1165         -DE/DX =    0.0                 !
! A18   A(1,2,4)               90.2099         -DE/DX =    0.0                 !
! A19   A(1,2,11)              98.9089         -DE/DX =    0.0                 !
! A20   A(1,2,12)             131.5            -DE/DX =    0.0                 !
! A21   A(1,2,13)             120.0522         -DE/DX =    0.0                 !
! A22   A(1,2,14)             119.9852         -DE/DX =    0.0                 !
! A23   A(4,2,11)              46.5393         -DE/DX =    0.0                 !
! A24   A(4,2,12)              44.49           -DE/DX =    0.0                 !
! A25   A(4,2,13)              83.3596         -DE/DX =    0.0                 !
! A26   A(4,2,14)             118.2474         -DE/DX =    0.0                 !
! A27   A(11,2,12)             40.6755         -DE/DX =    0.0                 !
! A28   A(11,2,13)            116.9475         -DE/DX =    0.0                 !
! A29   A(11,2,14)             74.644          -DE/DX =    0.0                 !
! A30   A(12,2,13)             77.8409         -DE/DX =    0.0                 !
! A31   A(12,2,14)             80.5627         -DE/DX =    0.0                 !
! A32   A(13,2,14)            115.1638         -DE/DX =    0.0                 !
! A33   A(4,3,11)             120.6613         -DE/DX =    0.0                 !
! A34   A(4,3,12)             120.0232         -DE/DX =    0.0                 !
! A35   A(4,3,13)              94.0558         -DE/DX =    0.0                 !
! A36   A(4,3,14)             127.3507         -DE/DX =    0.0                 !
! A37   A(11,3,12)            114.4864         -DE/DX =    0.0                 !
! A38   A(11,3,13)            109.2312         -DE/DX =    0.0                 !
! A39   A(11,3,14)             69.5135         -DE/DX =    0.0                 !
! A40   A(12,3,13)             88.6205         -DE/DX =    0.0                 !
! A41   A(12,3,14)             91.9441         -DE/DX =    0.0                 !
! A42   A(13,3,14)             42.3516         -DE/DX =    0.0                 !
! A43   A(2,4,5)              121.3465         -DE/DX =    0.0                 !
! A44   A(2,4,6)               89.7903         -DE/DX =    0.0                 !
! A45   A(3,4,5)              118.6679         -DE/DX =    0.0                 !
! A46   A(3,4,6)              122.0341         -DE/DX =    0.0                 !
! A47   A(5,4,6)              117.9096         -DE/DX =    0.0                 !
! A48   A(1,6,4)               89.7901         -DE/DX =    0.0                 !
! A49   A(1,6,8)              121.3467         -DE/DX =    0.0                 !
! A50   A(4,6,7)              122.0341         -DE/DX =    0.0                 !
! A51   A(4,6,8)              117.9096         -DE/DX =    0.0                 !
! A52   A(7,6,8)              118.6679         -DE/DX =    0.0                 !
! A53   A(6,7,9)              120.0232         -DE/DX =    0.0                 !
! A54   A(6,7,10)             120.6613         -DE/DX =    0.0                 !
! A55   A(6,7,15)              94.0558         -DE/DX =    0.0                 !
! A56   A(6,7,16)             127.3506         -DE/DX =    0.0                 !
! A57   A(9,7,10)             114.4864         -DE/DX =    0.0                 !
! A58   A(9,7,15)              88.6207         -DE/DX =    0.0                 !
! A59   A(9,7,16)              91.9443         -DE/DX =    0.0                 !
! A60   A(10,7,15)            109.2309         -DE/DX =    0.0                 !
! A61   A(10,7,16)             69.5133         -DE/DX =    0.0                 !
! A62   A(15,7,16)             42.3515         -DE/DX =    0.0                 !
! D1    D(6,1,2,3)            -20.742          -DE/DX =    0.0                 !
! D2    D(6,1,2,4)              0.0            -DE/DX =    0.0                 !
! D3    D(6,1,2,11)           -45.918          -DE/DX =    0.0                 !
! D4    D(6,1,2,12)           -18.3309         -DE/DX =    0.0                 !
! D5    D(6,1,2,13)            82.445          -DE/DX =    0.0                 !
! D6    D(6,1,2,14)          -123.2664         -DE/DX =    0.0                 !
! D7    D(7,1,2,3)             -0.0001         -DE/DX =    0.0                 !
! D8    D(7,1,2,4)             20.742          -DE/DX =    0.0                 !
! D9    D(7,1,2,11)           -25.1761         -DE/DX =    0.0                 !
! D10   D(7,1,2,12)             2.4111         -DE/DX =    0.0                 !
! D11   D(7,1,2,13)           103.1869         -DE/DX =    0.0                 !
! D12   D(7,1,2,14)          -102.5244         -DE/DX =    0.0                 !
! D13   D(9,1,2,3)             -2.4112         -DE/DX =    0.0                 !
! D14   D(9,1,2,4)             18.3308         -DE/DX =    0.0                 !
! D15   D(9,1,2,11)           -27.5872         -DE/DX =    0.0                 !
! D16   D(9,1,2,12)            -0.0001         -DE/DX =    0.0                 !
! D17   D(9,1,2,13)           100.7758         -DE/DX =    0.0                 !
! D18   D(9,1,2,14)          -104.9356         -DE/DX =    0.0                 !
! D19   D(10,1,2,3)            25.176          -DE/DX =    0.0                 !
! D20   D(10,1,2,4)            45.918          -DE/DX =    0.0                 !
! D21   D(10,1,2,11)           -0.0001         -DE/DX =    0.0                 !
! D22   D(10,1,2,12)           27.5871         -DE/DX =    0.0                 !
! D23   D(10,1,2,13)          128.3629         -DE/DX =    0.0                 !
! D24   D(10,1,2,14)          -77.3484         -DE/DX =    0.0                 !
! D25   D(15,1,2,3)          -103.1869         -DE/DX =    0.0                 !
! D26   D(15,1,2,4)           -82.4449         -DE/DX =    0.0                 !
! D27   D(15,1,2,11)         -128.3629         -DE/DX =    0.0                 !
! D28   D(15,1,2,12)         -100.7758         -DE/DX =    0.0                 !
! D29   D(15,1,2,13)            0.0            -DE/DX =    0.0                 !
! D30   D(15,1,2,14)          154.2887         -DE/DX =    0.0                 !
! D31   D(16,1,2,3)           102.5243         -DE/DX =    0.0                 !
! D32   D(16,1,2,4)           123.2663         -DE/DX =    0.0                 !
! D33   D(16,1,2,11)           77.3483         -DE/DX =    0.0                 !
! D34   D(16,1,2,12)          104.9354         -DE/DX =    0.0                 !
! D35   D(16,1,2,13)         -154.2888         -DE/DX =    0.0                 !
! D36   D(16,1,2,14)           -0.0001         -DE/DX =    0.0                 !
! D37   D(2,1,6,4)              0.0            -DE/DX =    0.0                 !
! D38   D(2,1,6,8)           -123.0828         -DE/DX =    0.0                 !
! D39   D(9,1,6,4)           -160.3592         -DE/DX =    0.0                 !
! D40   D(9,1,6,8)             76.5581         -DE/DX =    0.0                 !
! D41   D(10,1,6,4)          -102.1158         -DE/DX =    0.0                 !
! D42   D(10,1,6,8)           134.8014         -DE/DX =    0.0                 !
! D43   D(15,1,6,4)           120.2482         -DE/DX =    0.0                 !
! D44   D(15,1,6,8)            -2.8345         -DE/DX =    0.0                 !
! D45   D(16,1,6,4)          -124.7021         -DE/DX =    0.0                 !
! D46   D(16,1,6,8)           112.2151         -DE/DX =    0.0                 !
! D47   D(1,2,4,5)            123.0828         -DE/DX =    0.0                 !
! D48   D(1,2,4,6)              0.0            -DE/DX =    0.0                 !
! D49   D(11,2,4,5)          -134.8015         -DE/DX =    0.0                 !
! D50   D(11,2,4,6)           102.1157         -DE/DX =    0.0                 !
! D51   D(12,2,4,5)           -76.5581         -DE/DX =    0.0                 !
! D52   D(12,2,4,6)           160.3591         -DE/DX =    0.0                 !
! D53   D(13,2,4,5)             2.8345         -DE/DX =    0.0                 !
! D54   D(13,2,4,6)          -120.2482         -DE/DX =    0.0                 !
! D55   D(14,2,4,5)          -112.2151         -DE/DX =    0.0                 !
! D56   D(14,2,4,6)           124.7022         -DE/DX =    0.0                 !
! D57   D(11,3,4,5)          -160.592          -DE/DX =    0.0                 !
! D58   D(11,3,4,6)            33.1448         -DE/DX =    0.0                 !
! D59   D(12,3,4,5)            -6.5509         -DE/DX =    0.0                 !
! D60   D(12,3,4,6)          -172.8141         -DE/DX =    0.0                 !
! D61   D(13,3,4,5)            84.1997         -DE/DX =    0.0                 !
! D62   D(13,3,4,6)           -82.0635         -DE/DX =    0.0                 !
! D63   D(14,3,4,5)           112.8115         -DE/DX =    0.0                 !
! D64   D(14,3,4,6)           -53.4517         -DE/DX =    0.0                 !
! D65   D(2,4,6,1)              0.0            -DE/DX =    0.0                 !
! D66   D(2,4,6,7)            -40.4359         -DE/DX =    0.0                 !
! D67   D(2,4,6,8)            125.9267         -DE/DX =    0.0                 !
! D68   D(3,4,6,1)             40.436          -DE/DX =    0.0                 !
! D69   D(3,4,6,7)              0.0            -DE/DX =    0.0                 !
! D70   D(3,4,6,8)            166.3627         -DE/DX =    0.0                 !
! D71   D(5,4,6,1)           -125.9267         -DE/DX =    0.0                 !
! D72   D(5,4,6,7)           -166.3626         -DE/DX =    0.0                 !
! D73   D(5,4,6,8)              0.0001         -DE/DX =    0.0                 !
! D74   D(4,6,7,9)            172.8141         -DE/DX =    0.0                 !
! D75   D(4,6,7,10)           -33.1446         -DE/DX =    0.0                 !
! D76   D(4,6,7,15)            82.0633         -DE/DX =    0.0                 !
! D77   D(4,6,7,16)            53.4515         -DE/DX =    0.0                 !
! D78   D(8,6,7,9)              6.5509         -DE/DX =    0.0                 !
! D79   D(8,6,7,10)           160.5921         -DE/DX =    0.0                 !
! D80   D(8,6,7,15)           -84.2            -DE/DX =    0.0                 !
! D81   D(8,6,7,16)          -112.8118         -DE/DX =    0.0                 !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


6. Vibrational frequencies


As the above table is shown, there is only one imaginary frequency that has a magnitude of 524.81 cm-1. The corresponding vibrational mode is shown below, and the motion is similar to that of the HF/3-21G optimised structure but slower.



7. Thermochemistry

Sum of electronic and zero-point Energies=           -234.403325
Sum of electronic and thermal Energies=              -234.396907
Sum of electronic and thermal Enthalpies=            -234.395963
Sum of electronic and thermal Free Energies=         -234.432892


8. HOMO/LUMO visialisation


9. Key information

Subject Job type Additional keywords Method Basis set Memory limit Energy Point group
Transition state Optimisation to a TS (Berny), calculate the force constants once Opt=NoEigen B3LYP 6-31G(d) Default -234.54389655 a.u. Cs


Diels Alder Reaction Between Cyclohexa-1,3-diene and Maleic Anhydride

Optimising the Reactants

(a) Optimisation of cyclohexa-1,3-diene

1. Optimising cyclohexa-1,3-diene using AM1 method

test molecule


2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000154     0.000450     YES
RMS     Force            0.000033     0.000300     YES
Maximum Displacement     0.001022     0.001800     YES
RMS     Displacement     0.000271     0.001200     YES
Predicted change in Energy=-1.882760D-07
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.342          -DE/DX =    0.0                 !
! R2    R(1,4)                  1.4477         -DE/DX =    0.0002              !
! R3    R(1,5)                  1.1            -DE/DX =    0.0                 !
! R4    R(2,6)                  1.1011         -DE/DX =    0.0                 !
! R5    R(2,9)                  1.4818         -DE/DX =   -0.0001              !
! R6    R(3,4)                  1.342          -DE/DX =    0.0                 !
! R7    R(3,7)                  1.1011         -DE/DX =    0.0                 !
! R8    R(3,12)                 1.4818         -DE/DX =   -0.0001              !
! R9    R(4,8)                  1.1            -DE/DX =    0.0                 !
! R10   R(9,10)                 1.1255         -DE/DX =    0.0                 !
! R11   R(9,11)                 1.1255         -DE/DX =    0.0                 !
! R12   R(9,12)                 1.5218         -DE/DX =   -0.0001              !
! R13   R(12,13)                1.1255         -DE/DX =    0.0                 !
! R14   R(12,14)                1.1255         -DE/DX =    0.0                 !
! A1    A(2,1,4)              120.6853         -DE/DX =    0.0                 !
! A2    A(2,1,5)              121.8282         -DE/DX =    0.0001              !
! A3    A(4,1,5)              117.4865         -DE/DX =    0.0                 !
! A4    A(1,2,6)              121.351          -DE/DX =    0.0001              !
! A5    A(1,2,9)              123.3892         -DE/DX =    0.0                 !
! A6    A(6,2,9)              115.2598         -DE/DX =    0.0                 !
! A7    A(4,3,7)              121.3511         -DE/DX =    0.0001              !
! A8    A(4,3,12)             123.3892         -DE/DX =    0.0                 !
! A9    A(7,3,12)             115.2598         -DE/DX =    0.0                 !
! A10   A(1,4,3)              120.6853         -DE/DX =    0.0                 !
! A11   A(1,4,8)              117.4865         -DE/DX =    0.0                 !
! A12   A(3,4,8)              121.8282         -DE/DX =    0.0001              !
! A13   A(2,9,10)             108.072          -DE/DX =    0.0                 !
! A14   A(2,9,11)             108.0596         -DE/DX =    0.0                 !
! A15   A(2,9,12)             115.9255         -DE/DX =    0.0                 !
! A16   A(10,9,11)            106.3594         -DE/DX =    0.0                 !
! A17   A(10,9,12)            109.0064         -DE/DX =    0.0                 !
! A18   A(11,9,12)            109.0031         -DE/DX =    0.0                 !
! A19   A(3,12,9)             115.9255         -DE/DX =    0.0                 !
! A20   A(3,12,13)            108.066          -DE/DX =    0.0                 !
! A21   A(3,12,14)            108.0656         -DE/DX =    0.0                 !
! A22   A(9,12,13)            109.0085         -DE/DX =    0.0                 !
! A23   A(9,12,14)            109.0009         -DE/DX =    0.0                 !
! A24   A(13,12,14)           106.3594         -DE/DX =    0.0                 !
! D1    D(4,1,2,6)           -179.9819         -DE/DX =    0.0                 !
! D2    D(4,1,2,9)              0.0265         -DE/DX =    0.0                 !
! D3    D(5,1,2,6)              0.01           -DE/DX =    0.0                 !
! D4    D(5,1,2,9)           -179.9816         -DE/DX =    0.0                 !
! D5    D(2,1,4,3)              0.0186         -DE/DX =    0.0                 !
! D6    D(2,1,4,8)           -179.991          -DE/DX =    0.0                 !
! D7    D(5,1,4,3)           -179.9737         -DE/DX =    0.0                 !
! D8    D(5,1,4,8)              0.0167         -DE/DX =    0.0                 !
! D9    D(1,2,9,10)          -122.7239         -DE/DX =    0.0                 !
! D10   D(1,2,9,11)           122.5658         -DE/DX =    0.0                 !
! D11   D(1,2,9,12)            -0.072          -DE/DX =    0.0                 !
! D12   D(6,2,9,10)            57.284          -DE/DX =    0.0                 !
! D13   D(6,2,9,11)           -57.4262         -DE/DX =    0.0                 !
! D14   D(6,2,9,12)           179.9359         -DE/DX =    0.0                 !
! D15   D(7,3,4,1)            179.9806         -DE/DX =    0.0                 !
! D16   D(7,3,4,8)             -0.0093         -DE/DX =    0.0                 !
! D17   D(12,3,4,1)            -0.0122         -DE/DX =    0.0                 !
! D18   D(12,3,4,8)           179.9979         -DE/DX =    0.0                 !
! D19   D(4,3,12,9)            -0.035          -DE/DX =    0.0                 !
! D20   D(4,3,12,13)          122.615          -DE/DX =    0.0                 !
! D21   D(4,3,12,14)         -122.6747         -DE/DX =    0.0                 !
! D22   D(7,3,12,9)           179.9718         -DE/DX =    0.0                 !
! D23   D(7,3,12,13)          -57.3782         -DE/DX =    0.0                 !
! D24   D(7,3,12,14)           57.3321         -DE/DX =    0.0                 !
! D25   D(2,9,12,3)             0.0727         -DE/DX =    0.0                 !
! D26   D(2,9,12,13)         -122.0793         -DE/DX =    0.0                 !
! D27   D(2,9,12,14)          122.2181         -DE/DX =    0.0                 !
! D28   D(10,9,12,3)          122.2309         -DE/DX =    0.0                 !
! D29   D(10,9,12,13)           0.0789         -DE/DX =    0.0                 !
! D30   D(10,9,12,14)        -115.6236         -DE/DX =    0.0                 !
! D31   D(11,9,12,3)         -122.0666         -DE/DX =    0.0                 !
! D32   D(11,9,12,13)         115.7814         -DE/DX =    0.0                 !
! D33   D(11,9,12,14)           0.0789         -DE/DX =    0.0                 !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


6. Key information

Molecule Job type Method Basis set Memory limit Energy Point group
Cyclohexa-1,3-diene Optimisation to a minimum Semi-empirical molecular orbital, AM1 ZDO Default 0.02795812 a.u. C2v


(b) Optimisation of maleic anhydride

1. Optimising maleic anhydride using AM1 method

test molecule


2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000110     0.000450     YES
RMS     Force            0.000027     0.000300     YES
Maximum Displacement     0.000207     0.001800     YES
RMS     Displacement     0.000083     0.001200     YES
Predicted change in Energy=-3.291002D-08
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.4975         -DE/DX =    0.0                 !
! R2    R(1,5)                  1.4092         -DE/DX =    0.0                 !
! R3    R(1,8)                  1.2166         -DE/DX =   -0.0001              !
! R4    R(2,3)                  1.3487         -DE/DX =    0.0                 !
! R5    R(2,6)                  1.0905         -DE/DX =    0.0                 !
! R6    R(3,4)                  1.4975         -DE/DX =    0.0                 !
! R7    R(3,7)                  1.0905         -DE/DX =    0.0                 !
! R8    R(4,5)                  1.4092         -DE/DX =    0.0                 !
! R9    R(4,9)                  1.2165         -DE/DX =    0.0001              !
! A1    A(2,1,5)              108.2684         -DE/DX =    0.0                 !
! A2    A(2,1,8)              134.6893         -DE/DX =    0.0                 !
! A3    A(5,1,8)              117.0423         -DE/DX =    0.0                 !
! A4    A(1,2,3)              107.9774         -DE/DX =    0.0                 !
! A5    A(1,2,6)              121.6488         -DE/DX =    0.0                 !
! A6    A(3,2,6)              130.3737         -DE/DX =    0.0                 !
! A7    A(2,3,4)              107.9768         -DE/DX =    0.0                 !
! A8    A(2,3,7)              130.3742         -DE/DX =    0.0                 !
! A9    A(4,3,7)              121.6489         -DE/DX =    0.0                 !
! A10   A(3,4,5)              108.2694         -DE/DX =    0.0                 !
! A11   A(3,4,9)              134.6883         -DE/DX =    0.0                 !
! A12   A(5,4,9)              117.0422         -DE/DX =    0.0                 !
! A13   A(1,5,4)              107.508          -DE/DX =    0.0                 !
! D1    D(5,1,2,3)             -0.0039         -DE/DX =    0.0                 !
! D2    D(5,1,2,6)           -180.0016         -DE/DX =    0.0                 !
! D3    D(8,1,2,3)            180.0008         -DE/DX =    0.0                 !
! D4    D(8,1,2,6)              0.0031         -DE/DX =    0.0                 !
! D5    D(2,1,5,4)              0.0013         -DE/DX =    0.0                 !
! D6    D(8,1,5,4)           -180.0024         -DE/DX =    0.0                 !
! D7    D(1,2,3,4)              0.0047         -DE/DX =    0.0                 !
! D8    D(1,2,3,7)            180.0023         -DE/DX =    0.0                 !
! D9    D(6,2,3,4)            180.0021         -DE/DX =    0.0                 !
! D10   D(6,2,3,7)             -0.0003         -DE/DX =    0.0                 !
! D11   D(2,3,4,5)             -0.004          -DE/DX =    0.0                 !
! D12   D(2,3,4,9)            180.0001         -DE/DX =    0.0                 !
! D13   D(7,3,4,5)           -180.0019         -DE/DX =    0.0                 !
! D14   D(7,3,4,9)              0.0023         -DE/DX =    0.0                 !
! D15   D(3,4,5,1)              0.0015         -DE/DX =    0.0                 !
! D16   D(9,4,5,1)           -180.0018         -DE/DX =    0.0                 !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


6. Key information

Molecule Job type Method Basis set Memory limit Energy Point group
Maleic anhydride Optimisation to a minimum Semi-empirical molecular orbital, AM1 ZDO Default -0.12182423 a.u. C2v


Optimising the Exo and Endo Transition Structures

(a) Optimisation of Exo transition state

1. Optimising exo transition state using AM1 method


The guess exo transition state was drawn as above by combining the optimised cyclohexa-1,3-diene and maleic anhydride structures with two partially formed C-C bonds of 2.2 Å bond length and modifying the cyclohexa-1,3-diene into envelope structre. The optimised structure is shown below, which has 2.17078 Å bond lengths for the partially formed bonds.


A GaussView image of a optimised exo transition state using AM1 method.
test molecule


2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000120     0.000450     YES
RMS     Force            0.000015     0.000300     YES
Maximum Displacement     0.001573     0.001800     YES
RMS     Displacement     0.000381     0.001200     YES
Predicted change in Energy=-8.526949D-08
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.3943         -DE/DX =    0.0                 !
! R2    R(1,4)                  1.3967         -DE/DX =    0.0001              !
! R3    R(1,5)                  1.0995         -DE/DX =    0.0                 !
! R4    R(2,8)                  1.1022         -DE/DX =    0.0                 !
! R5    R(2,12)                 1.4898         -DE/DX =    0.0                 !
! R6    R(2,17)                 2.1708         -DE/DX =    0.0                 !
! R7    R(3,4)                  1.3944         -DE/DX =    0.0                 !
! R8    R(3,7)                  1.1022         -DE/DX =    0.0                 !
! R9    R(3,9)                  1.4898         -DE/DX =    0.0                 !
! R10   R(3,16)                 2.17           -DE/DX =    0.0                 !
! R11   R(4,6)                  1.0995         -DE/DX =    0.0                 !
! R12   R(9,10)                 1.124          -DE/DX =    0.0                 !
! R13   R(9,11)                 1.1262         -DE/DX =    0.0                 !
! R14   R(9,12)                 1.5221         -DE/DX =    0.0                 !
! R15   R(12,13)                1.124          -DE/DX =    0.0                 !
! R16   R(12,14)                1.1262         -DE/DX =    0.0                 !
! R17   R(15,16)                1.4882         -DE/DX =    0.0                 !
! R18   R(15,19)                1.4096         -DE/DX =    0.0                 !
! R19   R(15,22)                1.2206         -DE/DX =    0.0                 !
! R20   R(16,17)                1.41           -DE/DX =    0.0001              !
! R21   R(16,20)                1.0926         -DE/DX =    0.0                 !
! R22   R(17,18)                1.4882         -DE/DX =    0.0                 !
! R23   R(17,21)                1.0926         -DE/DX =    0.0                 !
! R24   R(18,19)                1.4097         -DE/DX =    0.0                 !
! R25   R(18,23)                1.2206         -DE/DX =   -0.0001              !
! A1    A(2,1,4)              118.1251         -DE/DX =    0.0                 !
! A2    A(2,1,5)              120.7728         -DE/DX =    0.0                 !
! A3    A(4,1,5)              120.3832         -DE/DX =    0.0                 !
! A4    A(1,2,8)              120.4887         -DE/DX =    0.0                 !
! A5    A(1,2,12)             119.6892         -DE/DX =    0.0                 !
! A6    A(1,2,17)              92.7345         -DE/DX =    0.0                 !
! A7    A(8,2,12)             115.8574         -DE/DX =    0.0                 !
! A8    A(8,2,17)              97.5619         -DE/DX =    0.0                 !
! A9    A(12,2,17)             99.7893         -DE/DX =    0.0                 !
! A10   A(4,3,7)              120.4896         -DE/DX =    0.0                 !
! A11   A(4,3,9)              119.6761         -DE/DX =    0.0                 !
! A12   A(4,3,16)              92.7503         -DE/DX =    0.0                 !
! A13   A(7,3,9)              115.8531         -DE/DX =    0.0                 !
! A14   A(7,3,16)              97.5506         -DE/DX =    0.0                 !
! A15   A(9,3,16)              99.8269         -DE/DX =    0.0                 !
! A16   A(1,4,3)              118.1104         -DE/DX =    0.0                 !
! A17   A(1,4,6)              120.3904         -DE/DX =    0.0                 !
! A18   A(3,4,6)              120.7776         -DE/DX =    0.0                 !
! A19   A(3,9,10)             110.2442         -DE/DX =    0.0                 !
! A20   A(3,9,11)             107.3115         -DE/DX =    0.0                 !
! A21   A(3,9,12)             113.5186         -DE/DX =    0.0                 !
! A22   A(10,9,11)            106.2917         -DE/DX =    0.0                 !
! A23   A(10,9,12)            110.0253         -DE/DX =    0.0                 !
! A24   A(11,9,12)            109.1547         -DE/DX =    0.0                 !
! A25   A(2,12,9)             113.5172         -DE/DX =    0.0                 !
! A26   A(2,12,13)            110.2472         -DE/DX =    0.0                 !
! A27   A(2,12,14)            107.3179         -DE/DX =    0.0                 !
! A28   A(9,12,13)            110.0228         -DE/DX =    0.0                 !
! A29   A(9,12,14)            109.1596         -DE/DX =    0.0                 !
! A30   A(13,12,14)           106.2809         -DE/DX =    0.0                 !
! A31   A(16,15,19)           109.0509         -DE/DX =    0.0                 !
! A32   A(16,15,22)           134.8473         -DE/DX =    0.0                 !
! A33   A(19,15,22)           116.1017         -DE/DX =    0.0                 !
! A34   A(3,16,15)             99.5856         -DE/DX =    0.0                 !
! A35   A(3,16,17)            107.447          -DE/DX =    0.0                 !
! A36   A(3,16,20)             89.6269         -DE/DX =    0.0                 !
! A37   A(15,16,17)           106.9854         -DE/DX =    0.0                 !
! A38   A(15,16,20)           120.414          -DE/DX =    0.0                 !
! A39   A(17,16,20)           125.9738         -DE/DX =    0.0                 !
! A40   A(2,17,16)            107.4327         -DE/DX =    0.0                 !
! A41   A(2,17,18)             99.5939         -DE/DX =    0.0                 !
! A42   A(2,17,21)             89.6056         -DE/DX =    0.0                 !
! A43   A(16,17,18)           106.9892         -DE/DX =    0.0                 !
! A44   A(16,17,21)           125.9873         -DE/DX =    0.0                 !
! A45   A(18,17,21)           120.4114         -DE/DX =    0.0                 !
! A46   A(17,18,19)           109.049          -DE/DX =    0.0                 !
! A47   A(17,18,23)           134.8508         -DE/DX =    0.0                 !
! A48   A(19,18,23)           116.1            -DE/DX =    0.0                 !
! A49   A(15,19,18)           107.9169         -DE/DX =    0.0                 !
! D1    D(4,1,2,8)           -168.9629         -DE/DX =    0.0                 !
! D2    D(4,1,2,12)            34.3611         -DE/DX =    0.0                 !
! D3    D(4,1,2,17)           -68.5343         -DE/DX =    0.0                 !
! D4    D(5,1,2,8)              1.3593         -DE/DX =    0.0                 !
! D5    D(5,1,2,12)          -155.3167         -DE/DX =    0.0                 !
! D6    D(5,1,2,17)           101.7878         -DE/DX =    0.0                 !
! D7    D(2,1,4,3)              0.001          -DE/DX =    0.0                 !
! D8    D(2,1,4,6)            170.3452         -DE/DX =    0.0                 !
! D9    D(5,1,4,3)           -170.3604         -DE/DX =    0.0                 !
! D10   D(5,1,4,6)             -0.0161         -DE/DX =    0.0                 !
! D11   D(1,2,12,9)           -32.8475         -DE/DX =    0.0                 !
! D12   D(1,2,12,13)         -156.8011         -DE/DX =    0.0                 !
! D13   D(1,2,12,14)           87.8573         -DE/DX =    0.0                 !
! D14   D(8,2,12,9)           169.4331         -DE/DX =    0.0                 !
! D15   D(8,2,12,13)           45.4795         -DE/DX =    0.0                 !
! D16   D(8,2,12,14)          -69.8621         -DE/DX =    0.0                 !
! D17   D(17,2,12,9)           66.0171         -DE/DX =    0.0                 !
! D18   D(17,2,12,13)         -57.9365         -DE/DX =    0.0                 !
! D19   D(17,2,12,14)        -173.2782         -DE/DX =    0.0                 !
! D20   D(1,2,17,16)           59.3625         -DE/DX =    0.0                 !
! D21   D(1,2,17,18)          170.6887         -DE/DX =    0.0                 !
! D22   D(1,2,17,21)          -68.4985         -DE/DX =    0.0                 !
! D23   D(8,2,17,16)         -179.3895         -DE/DX =    0.0                 !
! D24   D(8,2,17,18)          -68.0632         -DE/DX =    0.0                 !
! D25   D(8,2,17,21)           52.7496         -DE/DX =    0.0                 !
! D26   D(12,2,17,16)         -61.3965         -DE/DX =    0.0                 !
! D27   D(12,2,17,18)          49.9298         -DE/DX =    0.0                 !
! D28   D(12,2,17,21)         170.7426         -DE/DX =    0.0                 !
! D29   D(7,3,4,1)            168.978          -DE/DX =    0.0                 !
! D30   D(7,3,4,6)             -1.3272         -DE/DX =    0.0                 !
! D31   D(9,3,4,1)            -34.3934         -DE/DX =    0.0                 !
! D32   D(9,3,4,6)            155.3014         -DE/DX =    0.0                 !
! D33   D(16,3,4,1)            68.5529         -DE/DX =    0.0                 !
! D34   D(16,3,4,6)          -101.7523         -DE/DX =    0.0                 !
! D35   D(4,3,9,10)           156.8999         -DE/DX =    0.0                 !
! D36   D(4,3,9,11)           -87.7508         -DE/DX =    0.0                 !
! D37   D(4,3,9,12)            32.9443         -DE/DX =    0.0                 !
! D38   D(7,3,9,10)           -45.4247         -DE/DX =    0.0                 !
! D39   D(7,3,9,11)            69.9246         -DE/DX =    0.0                 !
! D40   D(7,3,9,12)          -169.3803         -DE/DX =    0.0                 !
! D41   D(16,3,9,10)           57.9975         -DE/DX =    0.0                 !
! D42   D(16,3,9,11)          173.3467         -DE/DX =    0.0                 !
! D43   D(16,3,9,12)          -65.9581         -DE/DX =    0.0                 !
! D44   D(4,3,16,15)         -170.6853         -DE/DX =    0.0                 !
! D45   D(4,3,16,17)          -59.3622         -DE/DX =    0.0                 !
! D46   D(4,3,16,20)           68.4959         -DE/DX =    0.0                 !
! D47   D(7,3,16,15)           68.0644         -DE/DX =    0.0                 !
! D48   D(7,3,16,17)          179.3875         -DE/DX =    0.0                 !
! D49   D(7,3,16,20)          -52.7544         -DE/DX =    0.0                 !
! D50   D(9,3,16,15)          -49.9303         -DE/DX =    0.0                 !
! D51   D(9,3,16,17)           61.3928         -DE/DX =    0.0                 !
! D52   D(9,3,16,20)         -170.749          -DE/DX =    0.0                 !
! D53   D(3,9,12,2)            -0.0594         -DE/DX =    0.0                 !
! D54   D(3,9,12,13)          124.0161         -DE/DX =    0.0                 !
! D55   D(3,9,12,14)         -119.7207         -DE/DX =    0.0                 !
! D56   D(10,9,12,2)         -124.1339         -DE/DX =    0.0                 !
! D57   D(10,9,12,13)          -0.0584         -DE/DX =    0.0                 !
! D58   D(10,9,12,14)         116.2048         -DE/DX =    0.0                 !
! D59   D(11,9,12,2)          119.5912         -DE/DX =    0.0                 !
! D60   D(11,9,12,13)        -116.3333         -DE/DX =    0.0                 !
! D61   D(11,9,12,14)          -0.07           -DE/DX =    0.0                 !
! D62   D(19,15,16,3)         111.1286         -DE/DX =    0.0                 !
! D63   D(19,15,16,17)         -0.5575         -DE/DX =    0.0                 !
! D64   D(19,15,16,20)       -153.6227         -DE/DX =    0.0                 !
! D65   D(22,15,16,3)         -69.0334         -DE/DX =    0.0                 !
! D66   D(22,15,16,17)        179.2805         -DE/DX =    0.0                 !
! D67   D(22,15,16,20)         26.2153         -DE/DX =    0.0                 !
! D68   D(16,15,19,18)          0.915          -DE/DX =    0.0                 !
! D69   D(22,15,19,18)       -178.9571         -DE/DX =    0.0                 !
! D70   D(3,16,17,2)           -0.0033         -DE/DX =    0.0                 !
! D71   D(3,16,17,18)        -106.1796         -DE/DX =    0.0                 !
! D72   D(3,16,17,21)         102.6539         -DE/DX =    0.0                 !
! D73   D(15,16,17,2)         106.1681         -DE/DX =    0.0                 !
! D74   D(15,16,17,18)         -0.0083         -DE/DX =    0.0                 !
! D75   D(15,16,17,21)       -151.1748         -DE/DX =    0.0                 !
! D76   D(20,16,17,2)        -102.6938         -DE/DX =    0.0                 !
! D77   D(20,16,17,18)        151.1298         -DE/DX =    0.0                 !
! D78   D(20,16,17,21)         -0.0366         -DE/DX =    0.0                 !
! D79   D(2,17,18,19)        -111.1034         -DE/DX =    0.0                 !
! D80   D(2,17,18,23)          69.0593         -DE/DX =    0.0                 !
! D81   D(16,17,18,19)          0.5715         -DE/DX =    0.0                 !
! D82   D(16,17,18,23)       -179.2657         -DE/DX =    0.0                 !
! D83   D(21,17,18,19)        153.6686         -DE/DX =    0.0                 !
! D84   D(21,17,18,23)        -26.1687         -DE/DX =    0.0                 !
! D85   D(17,18,19,15)         -0.9202         -DE/DX =    0.0                 !
! D86   D(23,18,19,15)        178.9513         -DE/DX =    0.0                 !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


6. Vibrational frequencies


As the above table is shown, there is only one imaginary frequency that has a magnitude of 812.23 cm-1. The corresponding vibrational mode is shown below. Although the reactants different, the transition structure for reaction between cyclohexa-1,3-diene and maleic Anhydride has a similar vibrational motion as the transition state structure for reaction between cis-Butadiene and ethylene obtained earlier, that is, the two C atoms of maleic Anhydride and the two middle C atoms of cyclohexa-1,3-diene approach each other in a sychronised motion and facilitates two simultaneous C-C bonds formation.



7. Thermochemistry

Sum of electronic and zero-point Energies=              0.134881
Sum of electronic and thermal Energies=                 0.144882
Sum of electronic and thermal Enthalpies=               0.145826
Sum of electronic and thermal Free Energies=            0.099117


8. Key information

Transition state type Job type Additional keywords Method Basis set Memory limit Energy Point group
Exo Optimisation to a TS (Berny), calculate the force constants once Opt=NoEigen Semi-empirical molecular orbital, AM1 ZDO Default -0.05041976 a.u. Cs


(b) Optimisation of Endo transition state

1. Optimising endo transition state using AM1 method


The guess endo transition state was drawn in a similar way as for exo transition state.


A GaussView image of a optimised endo transition state using AM1 method.
test molecule


2. File link
The optimised file is linked to here.


3. General information


The gradient is less than 0.001, which means the optimisation is complete.


4. Real output

        Item               Value     Threshold  Converged?
Maximum Force            0.000013     0.000450     YES
RMS     Force            0.000003     0.000300     YES
Maximum Displacement     0.001115     0.001800     YES
RMS     Displacement     0.000199     0.001200     YES
Predicted change in Energy=-1.746014D-08
Optimization completed.
   -- Stationary point found.
                          ----------------------------
                          !   Optimized Parameters   !
                          ! (Angstroms and Degrees)  !
--------------------------                            --------------------------
! Name  Definition              Value          Derivative Info.                !
--------------------------------------------------------------------------------
! R1    R(1,2)                  1.393          -DE/DX =    0.0                 !
! R2    R(1,4)                  1.3972         -DE/DX =    0.0                 !
! R3    R(1,5)                  1.1006         -DE/DX =    0.0                 !
! R4    R(2,8)                  1.1024         -DE/DX =    0.0                 !
! R5    R(2,12)                 1.4905         -DE/DX =    0.0                 !
! R6    R(2,16)                 2.1623         -DE/DX =    0.0                 !
! R7    R(3,4)                  1.3931         -DE/DX =    0.0                 !
! R8    R(3,7)                  1.1024         -DE/DX =    0.0                 !
! R9    R(3,9)                  1.4905         -DE/DX =    0.0                 !
! R10   R(3,17)                 2.1624         -DE/DX =    0.0                 !
! R11   R(4,6)                  1.1006         -DE/DX =    0.0                 !
! R12   R(9,10)                 1.1224         -DE/DX =    0.0                 !
! R13   R(9,11)                 1.1261         -DE/DX =    0.0                 !
! R14   R(9,12)                 1.523          -DE/DX =    0.0                 !
! R15   R(12,13)                1.1224         -DE/DX =    0.0                 !
! R16   R(12,14)                1.1261         -DE/DX =    0.0                 !
! R17   R(15,16)                1.4892         -DE/DX =    0.0                 !
! R18   R(15,19)                1.409          -DE/DX =    0.0                 !
! R19   R(15,22)                1.2206         -DE/DX =    0.0                 !
! R20   R(16,17)                1.4085         -DE/DX =    0.0                 !
! R21   R(16,20)                1.0929         -DE/DX =    0.0                 !
! R22   R(17,18)                1.4892         -DE/DX =    0.0                 !
! R23   R(17,21)                1.0929         -DE/DX =    0.0                 !
! R24   R(18,19)                1.409          -DE/DX =    0.0                 !
! R25   R(18,23)                1.2206         -DE/DX =    0.0                 !
! A1    A(2,1,4)              118.2165         -DE/DX =    0.0                 !
! A2    A(2,1,5)              120.7313         -DE/DX =    0.0                 !
! A3    A(4,1,5)              120.3283         -DE/DX =    0.0                 !
! A4    A(1,2,8)              119.9715         -DE/DX =    0.0                 !
! A5    A(1,2,12)             119.926          -DE/DX =    0.0                 !
! A6    A(1,2,16)              96.7578         -DE/DX =    0.0                 !
! A7    A(8,2,12)             116.2572         -DE/DX =    0.0                 !
! A8    A(8,2,16)              98.0361         -DE/DX =    0.0                 !
! A9    A(12,2,16)             94.8221         -DE/DX =    0.0                 !
! A10   A(4,3,7)              119.972          -DE/DX =    0.0                 !
! A11   A(4,3,9)              119.9187         -DE/DX =    0.0                 !
! A12   A(4,3,17)              96.754          -DE/DX =    0.0                 !
! A13   A(7,3,9)              116.259          -DE/DX =    0.0                 !
! A14   A(7,3,17)              98.0409         -DE/DX =    0.0                 !
! A15   A(9,3,17)              94.8341         -DE/DX =    0.0                 !
! A16   A(1,4,3)              118.2165         -DE/DX =    0.0                 !
! A17   A(1,4,6)              120.3281         -DE/DX =    0.0                 !
! A18   A(3,4,6)              120.7314         -DE/DX =    0.0                 !
! A19   A(3,9,10)             110.0842         -DE/DX =    0.0                 !
! A20   A(3,9,11)             107.4557         -DE/DX =    0.0                 !
! A21   A(3,9,12)             113.5597         -DE/DX =    0.0                 !
! A22   A(10,9,11)            106.4376         -DE/DX =    0.0                 !
! A23   A(10,9,12)            109.9444         -DE/DX =    0.0                 !
! A24   A(11,9,12)            109.0785         -DE/DX =    0.0                 !
! A25   A(2,12,9)             113.5599         -DE/DX =    0.0                 !
! A26   A(2,12,13)            110.0786         -DE/DX =    0.0                 !
! A27   A(2,12,14)            107.4573         -DE/DX =    0.0                 !
! A28   A(9,12,13)            109.9455         -DE/DX =    0.0                 !
! A29   A(9,12,14)            109.0767         -DE/DX =    0.0                 !
! A30   A(13,12,14)           106.4425         -DE/DX =    0.0                 !
! A31   A(16,15,19)           109.018          -DE/DX =    0.0                 !
! A32   A(16,15,22)           134.7615         -DE/DX =    0.0                 !
! A33   A(19,15,22)           116.2183         -DE/DX =    0.0                 !
! A34   A(2,16,15)            100.0256         -DE/DX =    0.0                 !
! A35   A(2,16,17)            107.5789         -DE/DX =    0.0                 !
! A36   A(2,16,20)             88.616          -DE/DX =    0.0                 !
! A37   A(15,16,17)           106.9979         -DE/DX =    0.0                 !
! A38   A(15,16,20)           120.5094         -DE/DX =    0.0                 !
! A39   A(17,16,20)           126.1489         -DE/DX =    0.0                 !
! A40   A(3,17,16)            107.5757         -DE/DX =    0.0                 !
! A41   A(3,17,18)            100.0246         -DE/DX =    0.0                 !
! A42   A(3,17,21)             88.624          -DE/DX =    0.0                 !
! A43   A(16,17,18)           106.9995         -DE/DX =    0.0                 !
! A44   A(16,17,21)           126.1471         -DE/DX =    0.0                 !
! A45   A(18,17,21)           120.5072         -DE/DX =    0.0                 !
! A46   A(17,18,19)           109.0173         -DE/DX =    0.0                 !
! A47   A(17,18,23)           134.7619         -DE/DX =    0.0                 !
! A48   A(19,18,23)           116.2186         -DE/DX =    0.0                 !
! A49   A(15,19,18)           107.9644         -DE/DX =    0.0                 !
! D1    D(4,1,2,8)           -169.2253         -DE/DX =    0.0                 !
! D2    D(4,1,2,12)            33.6698         -DE/DX =    0.0                 !
! D3    D(4,1,2,16)           -65.8787         -DE/DX =    0.0                 !
! D4    D(5,1,2,8)              1.0586         -DE/DX =    0.0                 !
! D5    D(5,1,2,12)          -156.0462         -DE/DX =    0.0                 !
! D6    D(5,1,2,16)           104.4053         -DE/DX =    0.0                 !
! D7    D(2,1,4,3)             -0.0016         -DE/DX =    0.0                 !
! D8    D(2,1,4,6)            170.3222         -DE/DX =    0.0                 !
! D9    D(5,1,4,3)           -170.3262         -DE/DX =    0.0                 !
! D10   D(5,1,4,6)             -0.0024         -DE/DX =    0.0                 !
! D11   D(1,2,12,9)           -32.1894         -DE/DX =    0.0                 !
! D12   D(1,2,12,13)         -155.9427         -DE/DX =    0.0                 !
! D13   D(1,2,12,14)           88.5345         -DE/DX =    0.0                 !
! D14   D(8,2,12,9)           169.8841         -DE/DX =    0.0                 !
! D15   D(8,2,12,13)           46.1309         -DE/DX =    0.0                 !
! D16   D(8,2,12,14)          -69.392          -DE/DX =    0.0                 !
! D17   D(16,2,12,9)           68.4611         -DE/DX =    0.0                 !
! D18   D(16,2,12,13)         -55.2922         -DE/DX =    0.0                 !
! D19   D(16,2,12,14)        -170.815          -DE/DX =    0.0                 !
! D20   D(1,2,16,15)          -54.0347         -DE/DX =    0.0                 !
! D21   D(1,2,16,17)           57.522          -DE/DX =    0.0                 !
! D22   D(1,2,16,20)         -174.7939         -DE/DX =    0.0                 !
! D23   D(8,2,16,15)           67.6189         -DE/DX =    0.0                 !
! D24   D(8,2,16,17)          179.1756         -DE/DX =    0.0                 !
! D25   D(8,2,16,20)          -53.1403         -DE/DX =    0.0                 !
! D26   D(12,2,16,15)        -174.9754         -DE/DX =    0.0                 !
! D27   D(12,2,16,17)         -63.4188         -DE/DX =    0.0                 !
! D28   D(12,2,16,20)          64.2653         -DE/DX =    0.0                 !
! D29   D(7,3,4,1)            169.228          -DE/DX =    0.0                 !
! D30   D(7,3,4,6)             -1.0552         -DE/DX =    0.0                 !
! D31   D(9,3,4,1)            -33.6809         -DE/DX =    0.0                 !
! D32   D(9,3,4,6)            156.0359         -DE/DX =    0.0                 !
! D33   D(17,3,4,1)            65.8778         -DE/DX =    0.0                 !
! D34   D(17,3,4,6)          -104.4054         -DE/DX =    0.0                 !
! D35   D(4,3,9,10)           155.987          -DE/DX =    0.0                 !
! D36   D(4,3,9,11)           -88.494          -DE/DX =    0.0                 !
! D37   D(4,3,9,12)            32.231          -DE/DX =    0.0                 !
! D38   D(7,3,9,10)           -46.1            -DE/DX =    0.0                 !
! D39   D(7,3,9,11)            69.4191         -DE/DX =    0.0                 !
! D40   D(7,3,9,12)          -169.8559         -DE/DX =    0.0                 !
! D41   D(17,3,9,10)           55.335          -DE/DX =    0.0                 !
! D42   D(17,3,9,11)          170.8541         -DE/DX =    0.0                 !
! D43   D(17,3,9,12)          -68.4209         -DE/DX =    0.0                 !
! D44   D(4,3,17,16)          -57.5248         -DE/DX =    0.0                 !
! D45   D(4,3,17,18)           54.0322         -DE/DX =    0.0                 !
! D46   D(4,3,17,21)          174.7907         -DE/DX =    0.0                 !
! D47   D(7,3,17,16)         -179.1791         -DE/DX =    0.0                 !
! D48   D(7,3,17,18)          -67.6221         -DE/DX =    0.0                 !
! D49   D(7,3,17,21)           53.1364         -DE/DX =    0.0                 !
! D50   D(9,3,17,16)           63.4102         -DE/DX =    0.0                 !
! D51   D(9,3,17,18)          174.9673         -DE/DX =    0.0                 !
! D52   D(9,3,17,21)          -64.2743         -DE/DX =    0.0                 !
! D53   D(3,9,12,2)            -0.0271         -DE/DX =    0.0                 !
! D54   D(3,9,12,13)          123.7987         -DE/DX =    0.0                 !
! D55   D(3,9,12,14)         -119.8349         -DE/DX =    0.0                 !
! D56   D(10,9,12,2)         -123.8591         -DE/DX =    0.0                 !
! D57   D(10,9,12,13)          -0.0334         -DE/DX =    0.0                 !
! D58   D(10,9,12,14)         116.333          -DE/DX =    0.0                 !
! D59   D(11,9,12,2)          119.78           -DE/DX =    0.0                 !
! D60   D(11,9,12,13)        -116.3943         -DE/DX =    0.0                 !
! D61   D(11,9,12,14)          -0.0279         -DE/DX =    0.0                 !
! D62   D(19,15,16,2)         111.683          -DE/DX =    0.0                 !
! D63   D(19,15,16,17)         -0.3262         -DE/DX =    0.0                 !
! D64   D(19,15,16,20)       -153.9752         -DE/DX =    0.0                 !
! D65   D(22,15,16,2)         -68.8997         -DE/DX =    0.0                 !
! D66   D(22,15,16,17)        179.0912         -DE/DX =    0.0                 !
! D67   D(22,15,16,20)         25.4421         -DE/DX =    0.0                 !
! D68   D(16,15,19,18)          0.5266         -DE/DX =    0.0                 !
! D69   D(22,15,19,18)       -179.0122         -DE/DX =    0.0                 !
! D70   D(2,16,17,3)            0.0018         -DE/DX =    0.0                 !
! D71   D(2,16,17,18)        -106.723          -DE/DX =    0.0                 !
! D72   D(2,16,17,21)         101.5494         -DE/DX =    0.0                 !
! D73   D(15,16,17,3)         106.7284         -DE/DX =    0.0                 !
! D74   D(15,16,17,18)          0.0036         -DE/DX =    0.0                 !
! D75   D(15,16,17,21)       -151.7239         -DE/DX =    0.0                 !
! D76   D(20,16,17,3)        -101.5388         -DE/DX =    0.0                 !
! D77   D(20,16,17,18)        151.7364         -DE/DX =    0.0                 !
! D78   D(20,16,17,21)          0.0089         -DE/DX =    0.0                 !
! D79   D(3,17,18,19)        -111.6856         -DE/DX =    0.0                 !
! D80   D(3,17,18,23)          68.8971         -DE/DX =    0.0                 !
! D81   D(16,17,18,19)          0.3201         -DE/DX =    0.0                 !
! D82   D(16,17,18,23)       -179.0971         -DE/DX =    0.0                 !
! D83   D(21,17,18,19)        153.9643         -DE/DX =    0.0                 !
! D84   D(21,17,18,23)        -25.453          -DE/DX =    0.0                 !
! D85   D(17,18,19,15)         -0.5244         -DE/DX =    0.0                 !
! D86   D(23,18,19,15)        179.0144         -DE/DX =    0.0                 !
--------------------------------------------------------------------------------
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad


Both force and displacement are converged, indicating the success of optimisation.


5. Symmetry information


6. Vibrational frequencies


As the above table is shown, there is only one imaginary frequency that has a magnitude of 806.40 cm-1. The corresponding vibrational mode is shown below, and the endo transition structure has a similar vibrational motion as the exo transition structure obtained earlier.


7. Thermochemistry

Sum of electronic and zero-point Energies=              0.133495
Sum of electronic and thermal Energies=                 0.143684
Sum of electronic and thermal Enthalpies=               0.144628
Sum of electronic and thermal Free Energies=            0.097351


8. Key information

Transition state type Job type Additional keywords Method Basis set Memory limit Energy Point group
Endo Optimisation to a TS (Berny), calculate the force constants once Opt=NoEigen Semi-empirical molecular orbital, AM1 ZDO Default -0.05150479 a.u. Cs


(c) HOMO visialisation



They are both antisymmterical.