## Methylamide, CH3NH-

 H3 \ H5 - C1 - N2 / | H4 H6
The ion charge is -1.

## Atomic Charges and Dipole Moment

C1 charge= 0.671
N2 charge=-1.377
H3 charge=-0.184
H4 charge=-0.180
H5 charge=-0.207
H6 charge= 0.279
with a dipole moment of 3.06874 Debye

## Bond Lengths:

between C1 and N2: distance=1.453 ang___ between C1 and H3: distance=1.142 ang___
between C1 and H4: distance=1.141 ang___ between C1 and H5: distance=1.131 ang___
between N2 and H6: distance=1.031 ang___

## Bond Angles:

for H3-C1-N2: angle=114.9 deg___ for H4-C1-N2: angle=114.6 deg___
for H5-C1-N2: angle=117.4 deg___ for H6-N2-C1: angle=106.9 deg___

## Bond Orders (Mulliken):

between C1 and N2: order=0.875___ between C1 and H3: order=0.966___
between C1 and H4: order=0.967___ between C1 and H5: order=0.983___
between N2 and H6: order=0.912___

## 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. Please note that your structure can't be well described by a single Lewis structure, because of extensive delocalization.

### Hybridization in the Best Lewis Structure

1. A bonding orbital for C1-N2 with 1.9980 electrons
__has 47.09% C 1 character in a sp1.84 hybrid
__has 52.91% N 2 character in a sp2.40 hybrid

2. A bonding orbital for C1-H3 with 1.9932 electrons
__has 54.88% C 1 character in a s0.83 p3 hybrid
__has 45.12% H 3 character in a s orbital

3. A bonding orbital for C1-H4 with 1.9931 electrons
__has 54.93% C 1 character in a s0.83 p3 hybrid
__has 45.07% H 4 character in a s orbital

4. A bonding orbital for C1-H5 with 1.9954 electrons
__has 54.68% C 1 character in a s0.84 p3 hybrid
__has 45.32% H 5 character in a s orbital

5. A bonding orbital for N2-H6 with 1.9830 electrons
__has 62.89% N 2 character in a s0.84 p3 hybrid
__has 37.11% H 6 character in a s orbital

8. A lone pair orbital for N2 with 1.9681 electrons

9. A lone pair orbital for N2 with 1.8968 electrons
__made from a p-pi orbital ( 99.94% p 0.06% d)

-With core pairs on: C 1 N 2 -

#### 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 lone pair donor orbital, 8, for N2 with the antibonding acceptor orbital, 71, for C1-H5 is 41.4 kJ/mol.

The interaction of the second lone pair donor orbital, 9, for N2 with the antibonding acceptor orbital, 69, for C1-H3 is 77.7 kJ/mol.

The interaction of the second lone pair donor orbital, 9, for N2 with the antibonding acceptor orbital, 70, for C1-H4 is 74.9 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.

13 ----- 9.183
12 ----- 8.975

11 ----- 7.621
10 ----- 7.253

9 -^-v- 3.520

8 -^-v- 1.857

7 -^-v- -2.226

6 -^-v- -3.127

5 -^-v- -3.838

4 -^-v- -8.477

3 -^-v- -12.75

2 -^-v- -260.3

1 -^-v- -367.7

## 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 = -95.2272671785 Hartrees