## O-dehydro-acetic acid cation, CH3COO+

 H3 O7 \ / H5 - C1 - C2 / \ H4 O6
The ion charge is 1.

## Atomic Charges and Dipole Moment

C1 charge=-0.521
C2 charge= 0.599
H3 charge= 0.276
H4 charge= 0.277
H5 charge= 0.276
O6 charge= 0.047
O7 charge= 0.045
with a dipole moment of 4.12721 Debye

## Bond Lengths:

between C1 and C2: distance=1.435 ang___ between C1 and H3: distance=1.108 ang___
between C1 and H4: distance=1.116 ang___ between C1 and H5: distance=1.105 ang___
between C2 and O6: distance=1.297 ang___ between C2 and O7: distance=1.299 ang___
between O6 and O7: distance=1.651 ang___

## Bond Angles:

for H3-C1-C2: angle=110.0 deg___ for H4-C1-C2: angle=107.4 deg___
for H5-C1-C2: angle=110.7 deg___ for O6-C2-C1: angle=140.5 deg___
for O7-C2-C1: angle=140.5 deg___

## Bond Orders (Mulliken):

between C1 and C2: order=0.890___ between C1 and H3: order=0.914___
between C1 and H4: order=0.884___ between C1 and H5: order=0.920___
between C2 and O6: order=1.225___ between C2 and O7: order=1.222___
between O6 and O7: order=0.773___

## 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-C2 with 1.9971 electrons
__has 45.22% C 1 character in a s0.93 p3 hybrid
__has 54.78% C 2 character in a sp1.08 hybrid

2. A bonding orbital for C1-H3 with 1.9626 electrons
__has 65.08% C 1 character in a sp2.86 hybrid
__has 34.92% H 3 character in a s orbital

3. A bonding orbital for C1-H4 with 1.9349 electrons
__has 65.41% C 1 character in a s0.95 p3 hybrid
__has 34.59% H 4 character in a s orbital

4. A bonding orbital for C1-H5 with 1.9714 electrons
__has 64.93% C 1 character in a sp2.76 hybrid
__has 35.07% H 5 character in a s orbital

5. A bonding orbital for C2-O6 with 1.9915 electrons
__has 11.40% C 2 character in a s0.06 p3 d0.05 hybrid
__has 88.60% O 6 character in a p3 hybrid

6. A bonding orbital for C2-O6 with 1.9651 electrons
__has 33.07% C 2 character in a s0.95 p3 hybrid
__has 66.93% O 6 character in a sp2.77 hybrid

7. A bonding orbital for C2-O7 with 1.9737 electrons
__has 33.73% C 2 character in a sp2.82 hybrid
__has 66.27% O 7 character in a sp2.75 hybrid

8. A bonding orbital for O6-O7 with 1.9502 electrons
__has 50.02% O 6 character in a p3 hybrid
__has 49.98% O 7 character in a p3 hybrid

13. A lone pair orbital for O6 with 1.9889 electrons

14. A lone pair orbital for O7 with 1.9889 electrons

15. A lone pair orbital for O7 with 1.8014 electrons

111. A antibonding orbital for C2-O6 with 0.2576 electrons
__has 88.60% C 2 character in a s0.06 p3 d0.05 hybrid
__has 11.40% O 6 character in a p3 hybrid

-With core pairs on: C 1 C 2 O 6 O 7 -

#### 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 C1-H3 with the second antibonding acceptor orbital, 112, for C2-O6 is 45.4 kJ/mol.

The interaction of bonding donor orbital, 3, for C1-H4 with the antibonding acceptor orbital, 111, for C2-O6 is 95.5 kJ/mol.

The interaction of bonding donor orbital, 4, for C1-H5 with the antibonding acceptor orbital, 113, for C2-O7 is 43.0 kJ/mol.

The interaction of the second bonding donor orbital, 6, for C2-O6 with the antibonding acceptor orbital, 111, for C2-O6 is 38.3 kJ/mol.

The interaction of the second bonding donor orbital, 6, for C2-O6 with the antibonding acceptor orbital, 114, for O6-O7 is 51.6 kJ/mol.

The interaction of bonding donor orbital, 7, for C2-O7 with the antibonding acceptor orbital, 114, for O6-O7 is 53.4 kJ/mol.

The interaction of bonding donor orbital, 8, for O6-O7 with the antibonding acceptor orbital, 107, for C1-C2 is 85.4 kJ/mol.

The interaction of bonding donor orbital, 8, for O6-O7 with the second antibonding acceptor orbital, 112, for C2-O6 is 61.1 kJ/mol.

The interaction of bonding donor orbital, 8, for O6-O7 with the antibonding acceptor orbital, 113, for C2-O7 is 62.8 kJ/mol.

The interaction of lone pair donor orbital, 13, for O6 with the antibonding acceptor orbital, 107, for C1-C2 is 21.5 kJ/mol.

The interaction of lone pair donor orbital, 14, for O7 with the antibonding acceptor orbital, 107, for C1-C2 is 21.7 kJ/mol.

The interaction of the second lone pair donor orbital, 15, for O7 with the antibonding acceptor orbital, 111, for C2-O6 is 366. kJ/mol.

The interaction of the second lone pair donor orbital, 15, for O7 with the antibonding acceptor orbital, 113, for C2-O7 is 55.1 kJ/mol.

The interaction of antibonding donor orbital, 111, for C2-O6 with the second antibonding acceptor orbital, 112, for C2-O6 is 21.0 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.

19 ----- -4.494

18 ----- -5.437

17 ----- -10.33

16 ----- -13.44

15 -^-v- -15.52

14 -^-v- -17.13
13 -^-v- -17.23

12 -^-v- -18.29

11 -^-v- -19.68

10 -^-v- -20.44

9 -^-v- -20.57

8 -^-v- -22.05

7 -^-v- -26.91

6 -^-v- -31.82

5 -^-v- -38.82

4 -^-v- -274.1

3 -^-v- -279.1

2 -^-v- -517.8
1 -^-v- -517.8

## 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 = -228.0993540382 Hartrees