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Rep:Mod:TPD17 01356675

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NH3 Optimisation

Molecule: Ammonia, NH3

Calculation Method: RB3LYP

Basis Set: 6-31G(d,p)

E(RB3LYP): -56.55776873 a.u.

RMS Gradient Norm: 0.00000485 a.u.

Point Group: C3V

Bond Length: 1.01798

Bond Angle: 105.741


         Item               Value     Threshold  Converged?
 Maximum Force            0.000004     0.000450     YES
 RMS     Force            0.000004     0.000300     YES
 Maximum Displacement     0.000072     0.001800     YES
 RMS     Displacement     0.000035     0.001200     YES
 Predicted change in Energy=-5.986274D-10
 Optimization completed.
Ammonia

File:TORIN DE GROOT NH3 OPT 01356675.LOG

NH3 Vibrations


How many modes do you expect from the 3N-6 rule? 6
Which modes are degenerate (ie have the same energy)? 2&3 and 5&6
Which modes are "bending" vibrations and which are "bond stretch" vibrations? Bend:1,2,3 Stretch:4,5,6
Which mode is highly symmetric? 4
One mode is known as the "umbrella" mode, which one is this? 1
How many bands would you expect to see in an experimental spectrum of gaseous ammonia? 2

Charge on Nitrogen:-1.125
Charge on Hydrogens 0.375
Nitrogen is expected to have a negative charge and the hydrogens are expected to be positive because nitrogen is more electronegative than hydrogen.

N2 Optimisation

Molecule: Nitrogen, N2

Calculation Method: RB3LYP

Basis Set: 6-31G(d,p)

E(RB3LYP): -109.52412868 a.u.

RMS Gradient Norm: 0.00000003 a.u.

Point Group: D*H

       Item               Value     Threshold  Converged?
 Maximum Force            0.000000     0.000450     YES
 RMS     Force            0.000000     0.000300     YES
 Maximum Displacement     0.000000     0.001800     YES
 RMS     Displacement     0.000000     0.001200     YES

N2 Vibrations

Vibrations:1 at 2457.33

Nitrogen

File:N2OPTTPD17.LOG

H2 Optimisation

Molecule: Hydrogen, H2

Calculation Method: RB3LYP

Basis Set: 6-31G(d,p)

E(RB3LYP): -1.17853936 a.u.

RMS Gradient Norm: 0.00000017 a.u.

Point Group: D*H

        Item               Value     Threshold  Converged?
 Maximum Force            0.000000     0.000450     YES
 RMS     Force            0.000000     0.000300     YES
 Maximum Displacement     0.000000     0.001800     YES
 RMS     Displacement     0.000001     0.001200     YES

Vibrations:1 at 4465.68

Hydrogen

File:H2 OPT TPD17.LOG

Energy calculation

E(NH3)= -56.55776873 a.u
2*E(NH3)=-113.11553746 a.u
E(N2)=-109.52412868 a.u
E(H2)=-1.17853936 a.u
3*E(H2)=-3.53561808 a.u
ΔE=2*E(NH3)-[E(N2)+3*E(H2)]=-0.05579069999998865 a.u = -146.47849400811018 kJ/mol 
ΔE=-146.48kJ/mol so Ammonia is more stable than its gaseous reactants

HCl analysis

Molecule: HCl

Calculation Method: RB3LYP

Basis Set: 6-31G(d,p)

E(RB3LYP): -460.80077875 a.u.

RMS Gradient Norm: 0.00005211 a.u.

Point Group: C*V

         Item               Value     Threshold  Converged?
 Maximum Force            0.000090     0.000450     YES
 RMS     Force            0.000090     0.000300     YES
 Maximum Displacement     0.000139     0.001800     YES
 RMS     Displacement     0.000197     0.001200     YES

1 vibration at 2956.80 Charge on Cl atom:-0.284 Charge on H atom:0.284

HCl

File:HCLTEST OPT TPD17.LOG

The 1s orbital of the Chlorine atom, a non bonding orbital

The 2px orbital of the Chlorine atom, a non bonding orbital

The sigma orbital of the hydrogen 1s orbital and the 3s orbital of the Chlorine atom, a bonding orbital

The sigma orbital of the HCl from the 1s orbital from the hydrogen atom and the 3pz orbital from the Chlorine atom, a bonding orbital

The sigma star orbital of the HCl, an out of phase combination of the hydrogen 1s orbital and chlorine 3pz orbital, an anti-bonding orbital, the LUMO

Extra molecule CF4 analysis

Molecule      CF<sub>4</sub>
Calculation Method	RB3LYP
Basis Set	6-31G(d,p)
E(RB3LYP)	-437.47627267	 a.u.
RMS Gradient Norm	0.00004048	 a.u.
Point Group	TD
         Item               Value     Threshold  Converged?
 Maximum Force            0.000078     0.000450     YES
 RMS     Force            0.000042     0.000300     YES
 Maximum Displacement     0.000133     0.001800     YES
 RMS     Displacement     0.000071     0.001200     YES

File:TPD17 CF4 OPT.LOG

tetrafluoromethane

The charge on the chlorine atom is 1.407. The charge on the fluorines is -0.352


One major IR peak,from vibrations 7,8 and 9 one very small one from 4 and 5