## H2PO3-, or -O(HO)PH->O, Hydrogen phosphite ion

 O3 \\ H5 - P1 - O2 || | O4 H6
The ion charge is -1.

## Atomic Charges and Dipole Moment

P1 charge= 1.079
O2 charge=-0.744
O3 charge=-0.761
O4 charge=-0.820
H5 charge=-0.145
H6 charge= 0.392
with a dipole moment of 2.97972 Debye

## Bond Lengths:

between P1 and O2: distance=1.718 ang___ between P1 and O3: distance=1.524 ang___
between P1 and O4: distance=1.535 ang___ between P1 and H5: distance=1.451 ang___
between O2 and O3: distance=2.641 ang___ between O2 and H6: distance=0.978 ang___
between O3 and O4: distance=2.706 ang___

## Bond Angles:

for O3-P1-O2: angle=108.9 deg___ for O4-P1-O2: angle=105.1 deg___
for H5-P1-O2: angle=97.81 deg___ for H6-O2-P1: angle=102.5 deg___

## Bond Orders (Mulliken):

between P1 and O2: order=0.783___ between P1 and O3: order=1.637___
between P1 and O4: order=1.560___ between P1 and H5: order=0.995___
between O2 and O3: order=-0.095___ between O2 and H6: order=0.868___
between O3 and O4: order=-0.187___

## 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 P1-O2 with 1.9864 electrons
__has 20.21% P 1 character in a s0.74 p3 d0.10 hybrid
__has 79.79% O 2 character in a sp2.88 hybrid

2. A bonding orbital for P1-O3 with 1.9889 electrons
__has 26.07% P 1 character in a sp2.26 d0.05 hybrid
__has 73.93% O 3 character in a sp2.08 hybrid

3. A bonding orbital for P1-O4 with 1.9875 electrons
__has 25.91% P 1 character in a sp2.37 d0.06 hybrid
__has 74.09% O 4 character in a sp2.14 hybrid

4. A bonding orbital for P1-H5 with 1.9686 electrons
__has 39.68% P 1 character in a s0.89 p3 d0.09 hybrid
__has 60.32% H 5 character in a s orbital

5. A bonding orbital for O2-H6 with 1.9926 electrons
__has 73.78% O 2 character in a s0.86 p3 hybrid
__has 26.22% H 6 character in a s orbital

14. A lone pair orbital for O2 with 1.9878 electrons

15. A lone pair orbital for O2 with 1.9682 electrons

16. A lone pair orbital for O3 with 1.9830 electrons

17. A lone pair orbital for O3 with 1.8770 electrons

18. A lone pair orbital for O3 with 1.8615 electrons
__made from a p-pi orbital ( 99.91% p 0.09% d)

19. A lone pair orbital for O4 with 1.9837 electrons

20. A lone pair orbital for O4 with 1.8840 electrons

21. A lone pair orbital for O4 with 1.8759 electrons
__made from a p-pi orbital ( 99.92% p 0.08% d)

111. A antibonding orbital for P1-O2 with 0.1756 electrons
__has 79.79% P 1 character in a s0.74 p3 d0.10 hybrid
__has 20.21% O 2 character in a sp2.88 hybrid

114. A antibonding orbital for P1-H5 with 0.1360 electrons
__has 60.32% P 1 character in a s0.89 p3 d0.09 hybrid
__has 39.68% H 5 character in a s orbital

-With core pairs on: P 1 P 1 P 1 P 1 P 1 O 2 O 3 O 4 -

#### 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, 3, for P1-O4 with the antibonding acceptor orbital, 111, for P1-O2 is 22.2 kJ/mol.

The interaction of bonding donor orbital, 4, for P1-H5 with the antibonding acceptor orbital, 111, for P1-O2 is 30.2 kJ/mol.

The interaction of bonding donor orbital, 4, for P1-H5 with the antibonding acceptor orbital, 112, for P1-O3 is 21.9 kJ/mol.

The interaction of bonding donor orbital, 4, for P1-H5 with the antibonding acceptor orbital, 113, for P1-O4 is 20.7 kJ/mol.

The interaction of the second lone pair donor orbital, 15, for O2 with the antibonding acceptor orbital, 112, for P1-O3 is 22.6 kJ/mol.

The interaction of the second lone pair donor orbital, 15, for O2 with the antibonding acceptor orbital, 114, for P1-H5 is 24.8 kJ/mol.

The interaction of the second lone pair donor orbital, 17, for O3 with the antibonding acceptor orbital, 113, for P1-O4 is 63.0 kJ/mol.

The interaction of the second lone pair donor orbital, 17, for O3 with the antibonding acceptor orbital, 114, for P1-H5 is 101. kJ/mol.

The interaction of the third lone pair donor orbital, 18, for O3 with the antibonding acceptor orbital, 111, for P1-O2 is 141. kJ/mol.

The interaction of the third lone pair donor orbital, 18, for O3 with the antibonding acceptor orbital, 113, for P1-O4 is 42.8 kJ/mol.

The interaction of the second lone pair donor orbital, 20, for O4 with the antibonding acceptor orbital, 112, for P1-O3 is 94.9 kJ/mol.

The interaction of the second lone pair donor orbital, 20, for O4 with the antibonding acceptor orbital, 114, for P1-H5 is 60.1 kJ/mol.

The interaction of the third lone pair donor orbital, 21, for O4 with the antibonding acceptor orbital, 111, for P1-O2 is 132. kJ/mol.

The interaction of the third lone pair donor orbital, 21, for O4 with the antibonding acceptor orbital, 114, for P1-H5 is 44.2 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.

25 ----- 7.151
24 ----- 6.998

23 ----- 6.201

22 ----- 5.480

21 -^-v- -0.947

20 -^-v- -1.259
19 -^-v- -1.341

18 -^-v- -1.863

17 -^-v- -2.612

16 -^-v- -3.660

15 -^-v- -4.524

14 -^-v- -5.416

13 -^-v- -6.523

12 -^-v- -9.117

11 -^-v- -17.30

10 -^-v- -18.29

9 -^-v- -20.35

8 -^-v- -119.5
7 -^-v- -119.5

6 -^-v- -119.7

5 -^-v- -167.1

4 -^-v- -499.7
3 -^-v- -499.8

2 -^-v- -501.6

1 -^-v- -2065.

## 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 = -568.5007629386 Hartrees