## HCOO-, Formate ion

 O3 \\ C1 = O2 / H4
The ion charge is -1.

## Atomic Charges and Dipole Moment

C1 charge= 0.728
O2 charge=-0.780
O3 charge=-0.779
H4 charge=-0.168
with a dipole moment of 1.33721 Debye

## Bond Lengths:

between C1 and O2: distance=1.272 ang___ between C1 and O3: distance=1.272 ang___
between C1 and H4: distance=1.147 ang___ between O2 and O3: distance=2.304 ang___
between O2 and H4: distance=2.041 ang___ between O3 and H4: distance=2.043 ang___

## Bond Angles:

for O3-C1-O2: angle=129.9 deg___ for H4-C1-O2: angle=114.9 deg___

## Bond Orders (Mulliken):

between C1 and O2: order=1.537___ between C1 and O3: order=1.536___
between C1 and H4: order=1.074___ between O2 and O3: order=-0.193___
between O2 and H4: order=-0.062___ between O3 and H4: order=-0.062___

## 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 C1-O2 with 1.9977 electrons
__has 35.47% C 1 character in a sp1.77 hybrid
__has 64.53% O 2 character in a sp1.80 hybrid

2. A bonding orbital for C1-O2 with 1.9981 electrons
__has 19.38% C 1 character in a p-pi orbital ( 99.28% p 0.72% d)
__has 80.62% O 2 character in a p-pi orbital ( 99.89% p 0.11% d)

3. A bonding orbital for C1-O3 with 1.9978 electrons
__has 35.47% C 1 character in a sp1.77 hybrid
__has 64.53% O 3 character in a sp1.80 hybrid

4. A bonding orbital for C1-H4 with 1.9910 electrons
__has 50.99% C 1 character in a sp2.42 hybrid
__has 49.01% H 4 character in a s orbital

8. A lone pair orbital for O2 with 1.9814 electrons

9. A lone pair orbital for O2 with 1.9108 electrons
__made from a p-pi orbital ( 99.93% p 0.06% d)

10. A lone pair orbital for O3 with 1.9814 electrons

11. A lone pair orbital for O3 with 1.9107 electrons
__made from a p-pi orbital ( 99.93% p 0.06% d)

12. A lone pair orbital for O3 with 1.6722 electrons
__made from a p-pi orbital ( 99.90% p 0.10% d)

76. A antibonding orbital for C1-O2 with 0.3158 electrons
__has 80.62% C 1 character in a p-pi orbital ( 99.28% p 0.72% d)
__has 19.38% O 2 character in a p-pi orbital ( 99.89% p 0.11% d)

-With core pairs on: C 1 O 2 O 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 the second lone pair donor orbital, 9, for O2 with the antibonding acceptor orbital, 77, for C1-O3 is 99.2 kJ/mol.

The interaction of the second lone pair donor orbital, 9, for O2 with the antibonding acceptor orbital, 78, for C1-H4 is 110. kJ/mol.

The interaction of the second lone pair donor orbital, 11, for O3 with the antibonding acceptor orbital, 75, for C1-O2 is 99.2 kJ/mol.

The interaction of the second lone pair donor orbital, 11, for O3 with the antibonding acceptor orbital, 78, for C1-H4 is 110. kJ/mol.

The interaction of the third lone pair donor orbital, 12, for O3 with the second antibonding acceptor orbital, 76, for C1-O2 is 666. 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.

16 ----- 9.613
15 ----- 9.178

14 ----- 7.927

13 ----- 5.708

12 -^-v- 0.484

11 -^-v- 0.403

10 -^-v- -0.225

9 -^-v- -3.586

8 -^-v- -3.765

7 -^-v- -4.582

6 -^-v- -7.216

5 -^-v- -17.12

4 -^-v- -19.18

3 -^-v- -262.5

2 -^-v- -499.0 1 -^-v- -499.0

## 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 = -189.2840120171 Hartrees