Mod1220
NH3 molecule
| N-H bond length | 1.01798 Å |
| H-N-H bond angle | 105.741 |
| Calculation Method | RB3LYP |
| Basis Set | 6-31G(d.p) |
| E(RB3LYP) | -56.55776873 a.u. |
| RMS gradient | 0.00000485a.u. |
| Point Group | C3V |
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 ! Name Definition Value Derivative Info. ! -------------------------------------------------------------------------------- ! R1 R(1,2) 1.018 -DE/DX = 0.0 ! ! R2 R(1,3) 1.018 -DE/DX = 0.0 ! ! R3 R(1,4) 1.018 -DE/DX = 0.0 ! ! A1 A(2,1,3) 105.7412 -DE/DX = 0.0 ! ! A2 A(2,1,4) 105.7412 -DE/DX = 0.0 ! ! A3 A(3,1,4) 105.7412 -DE/DX = 0.0 ! ! D1 D(2,1,4,3) -111.8571 -DE/DX = 0.0 !
NH3 molecule |
The optimisation file is liked to here
3 modes are expected from the 3N-6 rule.
Mode 2 and mode 3 are degenerate, mode 5 and mode 6 are degenerate.
Mode 1,2 and 3 are bending vibrations and mode 4,5,6 are bond stretch vibrations.
Mode 1 and 4 are highly symmetric.
Mode 1 is known as the umbrella mode.
Two bands are expected to be seen in a spectrum as mode 4,5,6 have very small intensities and mode 2 and 3 are degenerate.
-1.125 charges on N , 0.375 charges on H.
N is expected to have negative charge as it is more electronegative than H, which means it has a stronger ability to attract electrons.
N2 molecule
| N-N bond length | 1.1055 Å |
| N-N bond angle | 90 |
| Calculation Method | RB3LYP |
| Basis Set | 6-31G(d.p) |
| E(RB3LYP) | -109.52412868 a.u. |
| RMS gradient | 0.00000365a.u. |
| Point Group | D*H |
Item Value Threshold Converged? Maximum Force 0.000006 0.000450 YES RMS Force 0.000006 0.000300 YES Maximum Displacement 0.000002 0.001800 YES RMS Displacement 0.000003 0.001200 YES ! Name Definition Value Derivative Info. ! -------------------------------------------------------------------------------- ! R1 R(1,2) 1.1055 -DE/DX = 0.0 !
N2 molecule |
The optimisation file is liked to here
1 mode is expected from 3N-5 rule, which is stretch vibration.
It is highly symmetric.
Only one band is seen in spectrum.
Zero charge on both N atoms as there is no dipole in a diatomic molecule.
H2 Molecule
| H-H bond length | 0.74279 Å |
| H-H bond angle | 90 |
| Calculation Method | RB3LYP |
| Basis Set | 6-31G(d.p) |
| E(RB3LYP) | -1.17853930 a.u. |
| RMS gradient | 0.00012170a.u. |
| Point Group | D*H |
Item Value Threshold Converged? Maximum Force 0.000211 0.000450 YES RMS Force 0.000211 0.000300 YES Maximum Displacement 0.000278 0.001800 YES RMS Displacement 0.000393 0.001200 YES ! Name Definition Value Derivative Info. ! -------------------------------------------------------------------------------- ! R1 R(1,2) 0.7431 -DE/DX = -0.0002 !
H2 molecule |
The optimisation file is liked to here
1 mode is expected from 3N-5 rule, which is stretch vibration.
It is highly symmetric.
Only one band is seen in spectrum.
Zero charge on both H atoms as there is no dipole in a diatomic molecule.
Reaction Energy of haber process
N2 + 3H2 -> 2NH3
| E(NH3) | -56.55776873 a.u. |
| 2*E(NH3 | -113.1155375 a.u. |
| E(N2) | -109.52412868 a.u. |
| E(H2) | -1.17853930 a.u. |
| 3*E(H2) | -3.5356179 a.u. |
ΔE=2*E(NH3)-[E(N2)+3*E(H2)]= -0.05579092 a.u. = -146.479 kJ/mol
The ammonia product is more stable than the reactants as it has lower energy than reactants.
[| More information about Haber process]
Molecule S2
| S-S bond length | 1.92947 Å |
| S-S bond angle | 90 |
| Calculation Method | RB3LYP |
| Basis Set | 6-31G(d.p) |
| E(RB3LYP) | -796.32599779a.u. |
| RMS gradient | 0.00000670 a.u. |
| Point Group | D*H |
Item Value Threshold Converged? Maximum Force 0.000012 0.000450 YES RMS Force 0.000012 0.000300 YES Maximum Displacement 0.000020 0.001800 YES RMS Displacement 0.000028 0.001200 YES ! Name Definition Value Derivative Info. ! -------------------------------------------------------------------------------- ! R1 R(1,2) 1.9295 -DE/DX = 0.0 !
S2 molecule |
The optimisation file is liked to here
1 mode is expected from 3N-5 rule, which is stretch vibration.
It is highly symmetric.
Only one band is seen in spectrum.
Zero charge on both S atoms as there is no dipole in a diatomic molecule.
MOs of S2 molecule
| Molecular Orbitals | Description |
|---|---|
 |
The MO is the bonding combination of two 1s AOs. The orbital energy, -88.93663 a.u. is much deeper than the MOs formed from the valence shell AOs. These two AOs can hardly overlap, they are held tightly to the nuclei, so are not very involved with chemical bonding. The MO is occupied. |
 |
The MO is the bonding combination of two 2s AOs. The 2s orbital is larger than 1s orbital so they overlaps better than 1s orbital. Orbital energy, -7.99779 a.u. is much higher than the MO formed by 1s AOs but deeper than those MOs formed by the valence shell AOs. The MO is occupied. |
 |
The MO is the bonding combination of two 2p AOs which are perpendicular to the bonding. It is the pi interaction. The 2p AOs overlap better than 2s AOs, so the orbital energy, -5.96349 a.u. is higher than the MO formed by 2s AOs. As it is not the valence orbital, the combination contributes less to the chemical bonding overall. The MO is occupied. |
 |
The MO is the bonding combination of two 2p AOs which are along the bonding. It is the sigma interaction. The 2p AOs in a line overlaps slightly better than 2p AOs side by side, so the orbital energy, -5.96135 a.u. is slightly higher than the MO formed by pi interaction. As it is not the valence orbital, the combination contributes less to the chemical bonding overall. The MO is occupied. |
 |
The MO is the bonding combination of two 3s AOs. 3s is the valence orbital, so the overlap is much better than the overlaps of inside orbitals. Orbital energy, -0.083211a.u. is therefore high. The MO is involved in the chemical bonding. The MO is occupied. |
 |
The MO is the anti-bonding combination of two 3p orbital which are perpendicular to the bond. This is the highest occupied molecular orbital (HOMO) with energy -0.21843 a.u.. As 3p is the valence orbital , the MO contributes a lot in the chemical bonding. |