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NH3 Molecule

General Information

N-H bond distance = 1.01798 Å

H-N-H bond angle = 105.741°

Calculation Method: RB3LYP

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

Total Energy: -56.55776870 a.u.

RMS Gradient Norm: 0.00000485 a.u.

Point Group: C03V

Item Table


         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

Jmol 3D Model

NH3 Molecule


File:Dz417 nh3 1.LOG


Display Vibrations

Questions about Display Vibrations

1.How many modes do you expect from the 3N-6 rule?

 Modes = 3*4-6 = 6

2.Which modes are degenerated (i.e. have the same energy?)

 Modes 2&3 and modes 5&6 are degenerated.

3.Which modes are "bending" vibrations and which are "bond stretch" vibrations?

 Modes 1&2&3 are bending and modes 4&5&6 are stretching.

4.Which mode is highly symmetric?

 Mode 4 is highly symmetric.

5.One mode is known as the "umbrella" mode, which one is this?

 Mode 1 is the "umbrella" mode.

6.How many bands would you expect to see in an experimental spectrum of gaseous ammonia?

 There are 4 bands.

Charge

The charge on N atom is -1.125.

The charge on H atom is +0.375.

Since N atom is more electronegative than H atom, the charge on N atom is negative while that on H is positive.

H2 Molecule

General Information

H-H bond distance = 0.74279 Å

H-H bond angle = 180°

Calculation Method: RB3LYP

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

Total Energy: -1.17853936 a.u.

RMS Gradient Norm: 0.09719500

Point Group: D*H

Item Table


         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


Jmol 3D Model

H2 Molecule

File:DZ417 H2 1.LOG

Display Vibrations


N2 Molecule

General Information

N-N bond distance = 1.09200 Å

N-N bond angle = 180°

Calculation Method: RB3LYP

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

Total Energy: -109.52359111 a.u.

RMS Gradient Norm: 0.02473091 a.u.

Point Group: D*H

Item Table

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

Jmol 3D Model

N2 Molecule

File:DZ417 N2 1.LOG

Display Vibrations

Reaction Energies

   E(NH3) = -56.55776870 a.u.
   2*E(NH3) = -113.1155370 a.u.
   E(N2) = -109.52359111 a.u.
   E(H2) = -1.17853936 a.u.
   3*E(H2) = -3.53561808 a.u.
   ΔE = 2*E(NH3)-[E(N2)+3*E(H2)] = -113.1155370+113.05920919 = -0.05632781 a.u. = -147.89  kJ/mol
   
   Since the energy difference is negative, the ammonia product is more stable.

Project molecule--F2 Molecule

General Information

F-F bond distance = 1.16000 Å

F-F bond angle = 180°

Calculation Method: RB3LYP

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

Total Energy: -199.42620785 a.u.

RMS Gradient Norm: 0.23253407 a.u.

Point Group: D*H

Item Table


         Item              Value      Threshold  Converged?
 Maximum Force            0.000128     0.000450     YES 
 RMS     Force            0.000128     0.000300     YES 
 Maximum Displacement     0.000156     0.001800     YES
 RMS     Displacement     0.000221     0.001200     YES 

Jmol 3D Model

F2 Molecule

Display Vibrations

Charge

There is the same charge on 2 F atoms and F2 molecule does not carry on a overall charge.

Molecular Orbital

MO1

MO2

MO3

MO4

MO5

Summary

. MO1 and MO2 are bonding and anti-bonding orbitals respectively formed by 2s AOs of F atom. Both of them are occupied and they are sigma bonds.

. 2p AOs of F atom contribute to the formation of MO3, MO4 and MO5. MO3 and MO4 are occupied and bonding while MO5 is unoccupied and anti-bonding. To be specific, MO3 and MO5 are sigma MOs formed by 2 Py AOs and however, MO4 is pi MOs which is formed by 2 Px AOs.

.Since MO3 and MO4 are bonding, they have relatively low energy in HOMO region, at -0.58753 a.u. and -0.52332 a.u.

. Meanwhile, MO5 is the LUMO (Lowest Unoccupied Molecular Orbital) with a relatively low energy (-0.12679 a.u.)

. Bond order of F2 Molecule is 1 so it is less stable than N2 molecule.

Independence--ClF3 Molecule

General Information

Cl-F bond distance = 1.57000 Å

F-Cl-F bond angle = 90° (axial) & 180° (equatorial)

Calculation Method: RB3LYP

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

Total Energy: -759.43206418 a.u.

RMS Gradient Norm: 0.05217279 a.u.

Point Group: C2V

Item Table


         Item              Value       Threshold  Converged?
 Maximum Force            0.000050     0.000450      YES 
 RMS     Force            0.000028     0.000300      YES 
 Maximum Displacement     0.000204     0.001800      YES 
 RMS     Displacement     0.000134     0.001200      YES 

Jmol 3D Model

ClF3 Molecule


File:DZ417 CLF3 3.LOG

Display Vibrations

Charge

Charge on Cl atom: +1.225

Charge on equatorial F atom: -0.316

Charge on axial F atom: -0.454