## HOPHO-, H2PO2, Dihydroxyphosphine anion

 H3 - O1 H5 \ / P2 | O4
The ion charge is -1.

## Atomic Charges and Dipole Moment

O1 charge=-0.656
P2 charge=-0.311
H3 charge= 0.403
O4 charge=-0.511
H5 charge= 0.075
with a dipole moment of 2.76092 Debye

## Bond Lengths:

between O1 and P2: distance=1.827 ang___ between O1 and H3: distance=0.975 ang___
between P2 and O4: distance=1.563 ang___ between P2 and H5: distance=1.506 ang___

## Bond Angles:

for H3-O1-P2: angle=103.0 deg___ for O4-P2-O1: angle=109.1 deg___
for H5-P2-O1: angle=87.30 deg___

## Bond Orders (Mulliken):

between O1 and P2: order=0.521___ between O1 and H3: order=0.903___
between P2 and O4: order=1.264___ between P2 and H5: order=0.937___

## 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 O1-P2 with 1.9241 electrons
__has 85.25% O 1 character in a s0.89 p3 hybrid
__has 14.75% P 2 character in a s0.69 p3 d1.44 hybrid

2. A bonding orbital for O1-H3 with 1.9944 electrons
__has 71.87% O 1 character in a s0.79 p3 hybrid
__has 28.13% H 3 character in a s orbital

3. A bonding orbital for P2-O4 with 1.9538 electrons
__has 22.06% P 2 character in a s0.76 p3 d0.51 hybrid
__has 77.94% O 4 character in a sp2.75 hybrid

4. A bonding orbital for P2-O4 with 1.9473 electrons
__has 8.53% P 2 character in a s0.30 p3 d1.97 hybrid
__has 91.47% O 4 character in a s0.17 p3 hybrid

5. A bonding orbital for P2-H5 with 1.9182 electrons
__has 37.18% P 2 character in a s0.44 p3 d0.46 hybrid
__has 62.82% H 5 character in a s orbital

13. A lone pair orbital for O1 with 1.9947 electrons

14. A lone pair orbital for O1 with 1.9744 electrons
__made from a s0.09 p3 hybrid

15. A lone pair orbital for P2 with 1.9917 electrons

16. A lone pair orbital for O4 with 1.9905 electrons

17. A lone pair orbital for O4 with 1.9269 electrons

90. A antibonding orbital for P2-O4 with 0.1278 electrons
__has 91.47% P 2 character in a s0.30 p3 d1.97 hybrid
__has 8.53% O 4 character in a s0.17 p3 hybrid

-With core pairs on: O 1 P 2 P 2 P 2 P 2 P 2 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, 1, for O1-P2 with the antibonding acceptor orbital, 89, for P2-O4 is 76.2 kJ/mol.

The interaction of bonding donor orbital, 1, for O1-P2 with the second antibonding acceptor orbital, 90, for P2-O4 is 186. kJ/mol.

The interaction of bonding donor orbital, 1, for O1-P2 with the antibonding acceptor orbital, 91, for P2-H5 is 51.9 kJ/mol.

The interaction of bonding donor orbital, 2, for O1-H3 with the second antibonding acceptor orbital, 90, for P2-O4 is 20.5 kJ/mol.

The interaction of bonding donor orbital, 3, for P2-O4 with the antibonding acceptor orbital, 87, for O1-P2 is 92.1 kJ/mol.

The interaction of bonding donor orbital, 3, for P2-O4 with the second antibonding acceptor orbital, 90, for P2-O4 is 122. kJ/mol.

The interaction of the second bonding donor orbital, 4, for P2-O4 with the antibonding acceptor orbital, 87, for O1-P2 is 77.7 kJ/mol.

The interaction of the second bonding donor orbital, 4, for P2-O4 with the antibonding acceptor orbital, 89, for P2-O4 is 61.0 kJ/mol.

The interaction of the second bonding donor orbital, 4, for P2-O4 with the antibonding acceptor orbital, 91, for P2-H5 is 36.4 kJ/mol.

The interaction of bonding donor orbital, 5, for P2-H5 with the antibonding acceptor orbital, 87, for O1-P2 is 134. kJ/mol.

The interaction of bonding donor orbital, 5, for P2-H5 with the second antibonding acceptor orbital, 90, for P2-O4 is 201. kJ/mol.

The interaction of the second lone pair donor orbital, 14, for O1 with the antibonding acceptor orbital, 89, for P2-O4 is 24.6 kJ/mol.

The interaction of the second lone pair donor orbital, 17, for O4 with the antibonding acceptor orbital, 91, for P2-H5 is 71.9 kJ/mol.

The interaction of the second antibonding donor orbital, 90, for P2-O4 with the antibonding acceptor orbital, 87, for O1-P2 is 438. 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.

21 ----- 7.366
20 ----- 7.097

19 ----- 6.036

18 ----- 4.756

17 -^-v- 1.198

16 -^-v- -0.538

15 -^-v- -1.020

14 -^-v- -2.305

13 -^-v- -2.894

12 -^-v- -3.941

11 -^-v- -5.237

10 -^-v- -8.329

9 -^-v- -16.70

8 -^-v- -18.74

7 -^-v- -117.6

6 -^-v- -117.7

5 -^-v- -117.8

4 -^-v- -165.3

3 -^-v- -498.8

2 -^-v- -500.7

1 -^-v- -2063.

## 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 = -493.1633795838 Hartrees