## HN=N-, Diimide ion

 H3 N1 = N2
The ion charge is -1.

## Atomic Charges and Dipole Moment

N1 charge=-0.149
N2 charge=-0.300
H3 charge=-0.550
with a dipole moment of 4.25102 Debye

## Bond Lengths:

between N1 and N2: distance=1.152 ang___ between N1 and H3: distance=2.166 ang___
between N2 and H3: distance=2.907 ang___

## Bond Angles:

for H3-N1-N2: angle=119.2 deg___

## Bond Orders (Mulliken):

between N1 and N2: order=2.557___ between N1 and H3: order=-0.359___
between N2 and H3: order=0.744___

## 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 N1-N2 with 2.0000 electrons
__has 50.10% N 1 character in a p-pi orbital ( 99.58% p 0.42% d)
__has 49.90% N 2 character in a p-pi orbital ( 99.53% p 0.47% d)

2. A bonding orbital for N1-N2 with 1.9998 electrons
__has 48.74% N 1 character in a sp1.82 hybrid
__has 51.26% N 2 character in a sp1.53 hybrid

3. A bonding orbital for N1-N2 with 1.9994 electrons
__has 44.24% N 1 character in a p3 hybrid
__has 55.76% N 2 character in a p3 hybrid

6. A lone pair orbital for N1 with 1.9925 electrons

7. A lone pair orbital for N2 with 1.9914 electrons

8. A lone pair orbital for H3 with 1.8775 electrons

54. A antibonding orbital for N1-N2 with 0.1107 electrons
__has 55.76% N 1 character in a p3 hybrid
__has 44.24% N 2 character in a p3 hybrid

-With core pairs on: N 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 H3 with the second antibonding acceptor orbital, 53, for N1-N2 is 4.68 kJ/mol.

The interaction of lone pair donor orbital, 8, for H3 with the third antibonding acceptor orbital, 54, for N1-N2 is 108. 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.

12 ----- 11.85

11 ----- 10.11

10 ----- 5.103

9 ----- 4.415

8 -^-v- 3.273

7 -^-v- -2.896

6 -^-v- -3.868

5 -^-v- -4.122

4 -^-v- -6.267

3 -^-v- -19.93

2 -^-v- -372.1

1 -^-v- -372.7

## 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 = -110.0660694456 Hartrees