## CH3CN, Acetonitrile, Methylcyanide

 H3 \ H5 - C1 - C2 E N6 / H4
Tell me about the atomic charges, dipole moment, bond lengths, angles, bond orders,
molecular orbital energies, or total energy.
Tell me about the best Lewis structure.

## Atomic Charges and Dipole Moment

C1 charge=-0.565
C2 charge= 0.452
H3 charge= 0.200
H4 charge= 0.200
H5 charge= 0.200
N6 charge=-0.490
with a dipole moment of 4.12453 Debye

## Bond Lengths:

between C1 and C2: distance=1.459 ang___ between C1 and H3: distance=1.103 ang___
between C1 and H4: distance=1.103 ang___ between C1 and H5: distance=1.103 ang___
between C2 and N6: distance=1.169 ang___

## Bond Angles:

for H3-C1-C2: angle=110.3 deg___ for H4-C1-C2: angle=110.3 deg___
for H5-C1-C2: angle=110.3 deg___ for N6-C2-C1: angle=179.8 deg___

## Bond Orders (Mulliken):

between C1 and C2: order=0.756___ between C1 and H3: order=0.975___
between C1 and H4: order=0.975___ between C1 and H5: order=0.975___
between C2 and N6: order=2.720___

## Best Lewis Structure

The Lewis structure that is closest to your structure is determined. The hybridization of the atoms in this idealized Lewis structure is given in the table below.

### Hybridization in the Best Lewis Structure

1. A bonding orbital for C1-C2 with 1.9945 electrons
__has 49.37% C 1 character in a sp2.69 hybrid
__has 50.63% C 2 character in a sp0.91 hybrid

2. A bonding orbital for C1-H3 with 1.9777 electrons
__has 61.53% C 1 character in a s0.96 p3 hybrid
__has 38.47% H 3 character in a s orbital

3. A bonding orbital for C1-H4 with 1.9778 electrons
__has 61.53% C 1 character in a s0.96 p3 hybrid
__has 38.47% H 4 character in a s orbital

4. A bonding orbital for C1-H5 with 1.9777 electrons
__has 61.53% C 1 character in a s0.96 p3 hybrid
__has 38.47% H 5 character in a s orbital

5. A bonding orbital for C2-N6 with 1.9976 electrons
__has 43.22% C 2 character in a sp1.07 hybrid
__has 56.78% N 6 character in a sp1.14 hybrid

6. A bonding orbital for C2-N6 with 1.9897 electrons
__has 44.02% C 2 character in a p-pi orbital ( 99.77% p 0.23% d)
__has 55.98% N 6 character in a p-pi orbital ( 99.61% p 0.39% d)

7. A bonding orbital for C2-N6 with 1.9897 electrons
__has 44.02% C 2 character in a p-pi orbital ( 99.77% p 0.23% d)
__has 55.98% N 6 character in a p-pi orbital ( 99.61% p 0.39% d)

11. A lone pair orbital for N6 with 1.9702 electrons

-With core pairs on: C 1 C 2 N 6 -

#### Donor Acceptor Interactions in the Best Lewis Structure

The localized orbitals in your best Lewis structure can interact strongly. A filled bonding or lone pair orbital can act as a donor and an empty or filled bonding, antibonding, or lone pair orbital can act as an acceptor. These interactions can strengthen and weaken bonds. For example, a lone pair donor->antibonding acceptor orbital interaction will weaken the bond associated with the antibonding orbital. Conversly, an interaction with a bonding pair as the acceptor will strengthen the bond. Strong electron delocalization in your best Lewis structure will also show up as donor-acceptor interactions.
Interactions greater than 20 kJ/mol for bonding and lone pair orbitals are listed below.

The interaction of bonding donor orbital, 2, for C1-H3 with the second antibonding acceptor orbital, 89, for C2-N6 is 36.2 kJ/mol.

The interaction of bonding donor orbital, 3, for C1-H4 with the antibonding acceptor orbital, 88, for C2-N6 is 19.9 kJ/mol.

The interaction of bonding donor orbital, 3, for C1-H4 with the third antibonding acceptor orbital, 90, for C2-N6 is 27.0 kJ/mol.

The interaction of bonding donor orbital, 4, for C1-H5 with the third antibonding acceptor orbital, 90, for C2-N6 is 27.2 kJ/mol.

The interaction of lone pair donor orbital, 11, for N6 with the antibonding acceptor orbital, 84, for C1-C2 is 61.0 kJ/mol.

## Molecular Orbital Energies

The orbital energies are given in eV, where 1 eV=96.49 kJ/mol. Orbitals with very low energy are core 1s orbitals. More antibonding orbitals than you might expect are sometimes listed, because d orbitals are always included for heavy atoms and p orbitals are included for H atoms. Up spins are shown with a ^ and down spins are shown as v.

15 ----- 2.242

14 ----- 1.218

13 ----- -0.476 12 ----- -0.478

11 -^-v- -8.192 10 -^-v- -8.193

9 -^-v- -8.550

8 -^-v- -11.51 7 -^-v- -11.51

6 -^-v- -12.87

5 -^-v- -19.29

4 -^-v- -22.42

3 -^-v- -267.6
2 -^-v- -267.7

1 -^-v- -377.3

## Total Electronic Energy

The total electronic energy is a very large number, so by convention the units are given in atomic units, that is Hartrees (H). One Hartree is 2625.5 kJ/mol. The energy reference is for totally dissociated atoms. In other words, the reference state is a gas consisting of nuclei and electrons all at infinite distance from each other. The electronic energy includes all electric interactions and the kinetic energy of the electrons. This energy does not include translation, rotation, or vibration of the the molecule.

Total electronic energy = -132.7962123140 Hartrees