H3 H6 \ / C1 - C2 / \\ H4 O5
The multiplicity is 2.

## Atomic Charges and Dipole Moment

C1 charge=-0.372
C2 charge= 0.444
H3 charge= 0.164
H4 charge= 0.198
O5 charge=-0.441
H6 charge= 0.006
with a dipole moment of 3.15128 Debye

## Bond Lengths:

between C1 and C2: distance=1.430 ang___ between C1 and H3: distance=1.096 ang___
between C1 and H4: distance=1.096 ang___ between C1 and H6: distance=2.180 ang___
between C2 and O5: distance=1.255 ang___ between C2 and H6: distance=1.118 ang___

## Bond Angles:

for H3-C1-C2: angle=121.1 deg___ for H4-C1-C2: angle=119.2 deg___
for O5-C2-C1: angle=122.7 deg___ for H6-C2-C1: angle=117.1 deg___

## Bond Orders (Mulliken):

between C1 and C2: order=1.150___ between C1 and H3: order=0.951___
between C1 and H4: order=0.965___ between C1 and H6: order=-0.061___
between C2 and O5: order=1.465___ between C2 and H6: order=0.996___

## 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. The Lewis structure is built for the up and down electrons, separately. Note that the up and down structures can be very different.

### Hybridization in the Best Lewis Structure

#### Down Electrons

1. A bonding orbital for C1-C2 with 0.9992 electrons
__has 84.56% C 1 character in a p-pi orbital ( 99.96% p)
__has 15.44% C 2 character in a p-pi orbital ( 99.68% p 0.32% d)

2. A bonding orbital for C1-C2 with 0.9984 electrons
__has 52.21% C 1 character in a sp1.72 hybrid
__has 47.79% C 2 character in a sp1.69 hybrid

3. A bonding orbital for C1-H3 with 0.9953 electrons
__has 60.83% C 1 character in a sp2.16 hybrid
__has 39.17% H 3 character in a s orbital

4. A bonding orbital for C1-H4 with 0.9952 electrons
__has 61.30% C 1 character in a sp2.13 hybrid
__has 38.70% H 4 character in a s orbital

5. A bonding orbital for C2-O5 with 0.9991 electrons
__has 33.62% C 2 character in a sp2.08 hybrid
__has 66.38% O 5 character in a sp1.66 hybrid

6. A bonding orbital for C2-H6 with 0.9950 electrons
__has 56.08% C 2 character in a sp2.23 hybrid
__has 43.92% H 6 character in a s orbital

10. A lone pair orbital for O5 with 0.9933 electrons

11. A lone pair orbital for O5 with 0.9644 electrons

12. A lone pair orbital for O5 with 0.9085 electrons
__made from a p-pi orbital ( 99.90% p 0.10% d)

-With core pairs on: C 1 C 2 O 5 -

#### Up Electrons

1. A bonding orbital for C1-C2 with 0.9983 electrons
__has 47.00% C 1 character in a sp1.78 hybrid
__has 53.00% C 2 character in a sp1.61 hybrid

2. A bonding orbital for C1-H3 with 0.9961 electrons
__has 56.24% C 1 character in a sp2.13 hybrid
__has 43.76% H 3 character in a s orbital

3. A bonding orbital for C1-H4 with 0.9960 electrons
__has 56.81% C 1 character in a sp2.10 hybrid
__has 43.19% H 4 character in a s orbital

4. A bonding orbital for C2-O5 with 0.9990 electrons
__has 37.60% C 2 character in a sp2.10 hybrid
__has 62.40% O 5 character in a sp1.62 hybrid

5. A bonding orbital for C2-O5 with 0.9382 electrons
__has 67.29% C 2 character in a p-pi orbital ( 99.85% p 0.15% d)
__has 32.71% O 5 character in a p-pi orbital ( 99.75% p 0.25% d)

6. A bonding orbital for C2-H6 with 0.9946 electrons
__has 58.43% C 2 character in a sp2.31 hybrid
__has 41.57% H 6 character in a s orbital

11. A lone pair orbital for O5 with 0.9926 electrons

12. A lone pair orbital for O5 with 0.9615 electrons
__made from a p-pi orbital ( 99.93% p 0.06% d)

-With core pairs on: C 1 C 2 O 5 -

#### 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 bonding donor orbital, 5, for C2-O5 with the lone pair acceptor orbital, 10, for C1 is 113. kJ/mol.

The interaction of the second lone pair donor orbital, 12, for O5 with the antibonding acceptor orbital, 85, for C1-C2 is 38.6 kJ/mol.

The interaction of the second lone pair donor orbital, 12, for O5 with the antibonding acceptor orbital, 90, for C2-H6 is 56.7 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. Only the spin up electron orbital energies are given.

16 ----- 2.937

15 ----- 1.984

14 ----- 1.601

13 ----- -1.506

12 -^--- -6.291

11 -^-v- -6.618

10 -^-v- -10.11

9 -^-v- -10.27

8 -^-v- -11.14

7 -^-v- -12.34

6 -^-v- -14.37

5 -^-v- -18.90

4 -^-v- -25.90

3 -^-v- -267.9

2 -^-v- -268.7

1 -^-v- -506.7

## 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 = -153.2274345683 Hartrees