## Li2S, lithium sulfide

 LI1 - S3 - LI2
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

LI1 charge= 0.813
LI2 charge= 0.811
S3 charge=-1.625
with a dipole moment of 1.63843 Debye

## Bond Lengths:

between LI1 and S3: distance=2.179 ang___ between LI2 and S3: distance=2.191 ang___

## Bond Angles:

for S3-LI1-LI2: angle=8.015 deg___ for LI1-S3-LI2: angle=164.2 deg___

## Bond Orders (Mulliken):

between LI1 and S3: order=0.883___ between LI2 and S3: order=0.877___

## 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

10. A lone pair orbital for S3 with 1.9849 electrons
__made from a s0.68 p3 hybrid

11. A lone pair orbital for S3 with 1.9833 electrons
__made from a p-pi orbital (100.00% p)

12. A lone pair orbital for S3 with 1.9661 electrons

13. A lone pair orbital for S3 with 1.9631 electrons

-With core pairs on:Li 1 Li 2 S 3 S 3 S 3 S 3 S 3 -

#### 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, 10, for S3 with the lone pair acceptor orbital, 8, for Li1 is 5.10 kJ/mol.

The interaction of the third lone pair donor orbital, 12, for S3 with the lone pair acceptor orbital, 8, for Li1 is 47.1 kJ/mol.

The interaction of 4th lone pair donor orbital, 13, for S3 with the lone pair acceptor orbital, 8, for Li1 is 51.0 kJ/mol.

The interaction of lone pair donor orbital, 10, for S3 with the lone pair acceptor orbital, 9, for Li2 is 5.06 kJ/mol.

The interaction of the third lone pair donor orbital, 12, for S3 with the lone pair acceptor orbital, 9, for Li2 is 41.2 kJ/mol.

The interaction of 4th lone pair donor orbital, 13, for S3 with the lone pair acceptor orbital, 9, for Li2 is 59.0 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 ----- 0.836
14 ----- 0.822

13 ----- -1.006

12 ----- -1.397

11 -^-v- -3.293
10 -^-v- -3.311

9 -^-v- -4.518

8 -^-v- -12.88

7 -^-v- -50.41
6 -^-v- -50.43

5 -^-v- -150.6

4 -^-v- -150.9
3 -^-v- -150.9

2 -^-v- -203.7

1 -^-v- -2383.

## 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 = -413.3064254187 Hartrees