## N-methylmethaniminonium cation, CH3NH=CH2+ (see note)

 H7 / H8 - C6 H3 \\ / N1 - C2 / | \ H9 H5 H4
The ion charge is 1.

## Atomic Charges and Dipole Moment

N1 charge=-0.009
C2 charge=-0.332
H3 charge= 0.197
H4 charge= 0.203
H5 charge= 0.203
C6 charge=-0.062
H7 charge= 0.240
H8 charge= 0.220
H9 charge= 0.338
with a dipole moment of 1.44845 Debye

## Bond Lengths:

between N1 and C2: distance=1.474 ang___ between N1 and C6: distance=1.289 ang___
between N1 and H9: distance=1.033 ang___ between C2 and H3: distance=1.099 ang___
between C2 and H4: distance=1.104 ang___ between C2 and H5: distance=1.104 ang___
between C6 and H7: distance=1.097 ang___ between C6 and H8: distance=1.096 ang___

## Bond Angles:

for H3-C2-N1: angle=109.6 deg___ for H4-C2-N1: angle=108.7 deg___
for H5-C2-N1: angle=108.7 deg___ for C6-N1-C2: angle=126.0 deg___
for H7-C6-N1: angle=119.1 deg___ for H8-C6-N1: angle=119.7 deg___
for H9-N1-C2: angle=115.6 deg___

## Bond Orders (Mulliken):

between N1 and C2: order=0.741___ between N1 and C6: order=1.629___
between N1 and H9: order=0.822___ between C2 and H3: order=0.976___
between C2 and H4: order=0.944___ between C2 and H5: order=0.944___
between C6 and H7: order=0.958___ between C6 and H8: order=0.946___

## 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 N1-C2 with 1.9918 electrons
__has 66.09% N 1 character in a sp1.88 hybrid
__has 33.91% C 2 character in a s0.90 p3 hybrid

2. A bonding orbital for N1-C6 with 1.9966 electrons
__has 63.28% N 1 character in a sp1.55 hybrid
__has 36.72% C 6 character in a sp1.93 hybrid

3. A bonding orbital for N1-C6 with 1.9877 electrons
__has 72.07% N 1 character in a p-pi orbital ( 99.90% p 0.10% d)
__has 27.93% C 6 character in a p-pi orbital ( 99.59% p 0.41% d)

4. A bonding orbital for N1-H9 with 1.9844 electrons
__has 72.82% N 1 character in a sp2.79 hybrid
__has 27.18% H 9 character in a s orbital

5. A bonding orbital for C2-H3 with 1.9921 electrons
__has 60.82% C 2 character in a sp2.81 hybrid
__has 39.18% H 3 character in a s orbital

6. A bonding orbital for C2-H4 with 1.9853 electrons
__has 61.43% C 2 character in a sp2.91 hybrid
__has 38.57% H 4 character in a s orbital

7. A bonding orbital for C2-H5 with 1.9853 electrons
__has 61.43% C 2 character in a sp2.91 hybrid
__has 38.57% H 5 character in a s orbital

8. A bonding orbital for C6-H7 with 1.9897 electrons
__has 61.14% C 6 character in a sp2.02 hybrid
__has 38.86% H 7 character in a s orbital

9. A bonding orbital for C6-H8 with 1.9872 electrons
__has 61.43% C 6 character in a sp2.01 hybrid
__has 38.57% H 8 character in a s orbital

-With core pairs on: N 1 C 2 C 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, 8, for C6-H7 with the antibonding acceptor orbital, 103, for N1-H9 is 22.5 kJ/mol.

The interaction of bonding donor orbital, 9, for C6-H8 with the antibonding acceptor orbital, 100, for N1-C2 is 32.0 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.

16 ----- -3.229

15 ----- -3.921

14 ----- -5.010

13 ----- -9.207

12 -^-v- -14.66

11 -^-v- -15.65

10 -^-v- -16.24

9 -^-v- -17.45

8 -^-v- -18.58

7 -^-v- -19.84

6 -^-v- -22.36

5 -^-v- -24.62

4 -^-v- -31.06

3 -^-v- -273.1

2 -^-v- -274.8

1 -^-v- -386.3

## 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 = -134.3386483782 Hartrees

* N-dehydro-dimethylamine cation rearranges to this ion.