## diimine triplet, N2H2 triplet (see note*)

 H3 \ N1 = N2 - H4
The multiplicity is 3.

## Atomic Charges and Dipole Moment

N1 charge=-0.335
N2 charge=-0.335
H3 charge= 0.335
H4 charge= 0.335
with a dipole moment of 1.85208 Debye

## Bond Lengths:

between N1 and N2: distance=1.276 ang___ between N1 and H3: distance=1.039 ang___
between N2 and H4: distance=1.039 ang___

## Bond Angles:

for H3-N1-N2: angle=119.1 deg___ for H4-N2-N1: angle=119.0 deg___

## Bond Orders (Mulliken):

between N1 and N2: order=1.377___ between N1 and H3: order=0.862___
between N2 and H4: order=0.862___

## 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. The Lewis structure is built for the up and down electrons, separately. Note that the up and down structures can be very different.

### Hybridization in the Best Lewis Structure

#### Down Electrons

1. A bonding orbital for N1-N2 with 0.9986 electrons
__has 50.00% N 1 character in a sp2.22 hybrid
__has 50.00% N 2 character in a sp2.22 hybrid

2. A bonding orbital for N1-H3 with 0.9970 electrons
__has 65.42% N 1 character in a s0.83 p3 hybrid
__has 34.58% H 3 character in a s orbital

3. A bonding orbital for N2-H4 with 0.9970 electrons
__has 65.42% N 2 character in a s0.83 p3 hybrid
__has 34.58% H 4 character in a s orbital

6. A lone pair orbital for N1 with 0.9979 electrons

7. A lone pair orbital for N1 with 0.9799 electrons

8. A lone pair orbital for N2 with 0.9979 electrons

9. A lone pair orbital for N2 with 0.9799 electrons

-With core pairs on: N 1 N 2 -

#### Up Electrons

1. A bonding orbital for N1-N2 with 0.9989 electrons
__has 50.00% N 1 character in a sp2.19 hybrid
__has 50.00% N 2 character in a sp2.19 hybrid

2. A bonding orbital for N1-H3 with 0.9494 electrons
__has 67.75% N 1 character in a s0.67 p3 hybrid
__has 32.25% H 3 character in a s orbital

3. A bonding orbital for N2-H4 with 0.9493 electrons
__has 67.74% N 2 character in a s0.67 p3 hybrid
__has 32.26% H 4 character in a s orbital

6. A lone pair orbital for N1 with 0.8491 electrons

7. A lone pair orbital for N1 with 0.1872 electrons

8. A lone pair orbital for N2 with 0.8491 electrons

9. A lone pair orbital for N2 with 0.1872 electrons

-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 bonding donor orbital, 2, for N1-H3 with the second lone pair acceptor orbital, 9, for N2 is 55.3 kJ/mol.

The interaction of bonding donor orbital, 3, for N2-H4 with the second lone pair acceptor orbital, 7, for N1 is 55.3 kJ/mol.

The interaction of lone pair donor orbital, 6, for N1 with the second lone pair acceptor orbital, 9, for N2 is 218. kJ/mol.

The interaction of lone pair donor orbital, 8, for N2 with the second lone pair acceptor orbital, 7, for N1 is 218. 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. Only the spin up electron orbital energies are given.

13 ----- 6.422

12 ----- 4.623

11 ----- 1.626

10 ----- 1.431

9 -^--- -4.809

8 -^--- -5.294

7 -^-v- -9.826

6 -^-v- -10.70

5 -^-v- -13.73

4 -^-v- -17.76

3 -^-v- -25.38

2 -^-v- -378.8 1 -^-v- -378.8

## 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 = -110.6309681580 Hartrees

* Note: The diimine singlet state is lower in energy.