H8 H5 H7 \ | / H11 C3 - C4 | / | \ O1 - C2 H9 H6 \ H10
The multiplicity is 2.

## Atomic Charges and Dipole Moment

O1 charge=-0.459
C2 charge=-0.247
C3 charge= 0.130
C4 charge=-0.459
H5 charge= 0.113
H6 charge= 0.124
H7 charge= 0.125
H8 charge= 0.042
H9 charge= 0.034
H10 charge= 0.197
H11 charge= 0.398
with a dipole moment of 1.80516 Debye

## Bond Lengths:

between O1 and C2: distance=1.390 ang___ between O1 and H11: distance=0.978 ang___
between C2 and C3: distance=1.498 ang___ between C2 and H10: distance=1.096 ang___
between C3 and C4: distance=1.544 ang___ between C3 and H8: distance=1.113 ang___
between C3 and H9: distance=1.117 ang___ between C4 and H5: distance=1.103 ang___
between C4 and H6: distance=1.104 ang___ between C4 and H7: distance=1.104 ang___

## Bond Angles:

for C3-C2-O1: angle=119.9 deg___ for C4-C3-C2: angle=112.1 deg___
for H5-C4-C3: angle=110.5 deg___ for H6-C4-C3: angle=110.9 deg___
for H7-C4-C3: angle=111.3 deg___ for H8-C3-C2: angle=109.6 deg___
for H9-C3-C2: angle=110.9 deg___ for H10-C2-O1: angle=111.5 deg___
for H11-O1-C2: angle=108.7 deg___

## Bond Orders (Mulliken):

between O1 and C2: order=0.878___ between O1 and H11: order=0.859___
between C2 and C3: order=0.841___ between C2 and H10: order=0.968___
between C3 and C4: order=0.806___ between C3 and H8: order=0.970___
between C3 and H9: order=0.960___ between C4 and H5: order=0.989___
between C4 and H6: order=0.983___ between C4 and H7: order=0.984___

## 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 O1-C2 with 0.9978 electrons
__has 67.30% O 1 character in a sp2.29 hybrid
__has 32.70% C 2 character in a sp2.95 hybrid

2. A bonding orbital for O1-H11 with 0.9953 electrons
__has 73.81% O 1 character in a s0.81 p3 hybrid
__has 26.19% H11 character in a s orbital

3. A bonding orbital for C2-C3 with 0.9963 electrons
__has 49.34% C 2 character in a sp1.81 hybrid
__has 50.66% C 3 character in a sp2.68 hybrid

4. A bonding orbital for C2-H10 with 0.9923 electrons
__has 59.18% C 2 character in a sp2.32 hybrid
__has 40.82% H10 character in a s orbital

5. A bonding orbital for C3-C4 with 0.9958 electrons
__has 51.08% C 3 character in a sp2.44 hybrid
__has 48.92% C 4 character in a sp2.48 hybrid

6. A bonding orbital for C3-H8 with 0.9922 electrons
__has 58.12% C 3 character in a s0.87 p3 hybrid
__has 41.88% H 8 character in a s orbital

7. A bonding orbital for C3-H9 with 0.9950 electrons
__has 57.11% C 3 character in a s0.82 p3 hybrid
__has 42.89% H 9 character in a s orbital

8. A bonding orbital for C4-H5 with 0.9962 electrons
__has 59.39% C 4 character in a s0.93 p3 hybrid
__has 40.61% H 5 character in a s orbital

9. A bonding orbital for C4-H6 with 0.9961 electrons
__has 59.19% C 4 character in a s0.92 p3 hybrid
__has 40.81% H 6 character in a s orbital

10. A bonding orbital for C4-H7 with 0.9960 electrons
__has 59.38% C 4 character in a s0.94 p3 hybrid
__has 40.62% H 7 character in a s orbital

15. A lone pair orbital for O1 with 0.9951 electrons
__made from a s0.67 p3 hybrid

16. A lone pair orbital for O1 with 0.9916 electrons

17. A lone pair orbital for C2 with 0.9712 electrons
__made from a s0.33 p3 hybrid

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

#### Up Electrons

1. A bonding orbital for O1-C2 with 0.9983 electrons
__has 69.45% O 1 character in a sp2.06 hybrid
__has 30.55% C 2 character in a sp2.52 hybrid

2. A bonding orbital for O1-H11 with 0.9947 electrons
__has 73.39% O 1 character in a s0.79 p3 hybrid
__has 26.61% H11 character in a s orbital

3. A bonding orbital for C2-C3 with 0.9963 electrons
__has 45.12% C 2 character in a sp1.63 hybrid
__has 54.88% C 3 character in a sp2.60 hybrid

4. A bonding orbital for C2-H10 with 0.9939 electrons
__has 54.43% C 2 character in a sp2.05 hybrid
__has 45.57% H10 character in a s orbital

5. A bonding orbital for C3-C4 with 0.9954 electrons
__has 51.71% C 3 character in a sp2.56 hybrid
__has 48.29% C 4 character in a sp2.51 hybrid

6. A bonding orbital for C3-H8 with 0.9906 electrons
__has 59.27% C 3 character in a s0.83 p3 hybrid
__has 40.73% H 8 character in a s orbital

7. A bonding orbital for C3-H9 with 0.9839 electrons
__has 61.54% C 3 character in a s0.88 p3 hybrid
__has 38.46% H 9 character in a s orbital

8. A bonding orbital for C4-H5 with 0.9964 electrons
__has 59.26% C 4 character in a s0.94 p3 hybrid
__has 40.74% H 5 character in a s orbital

9. A bonding orbital for C4-H6 with 0.9962 electrons
__has 59.05% C 4 character in a s0.93 p3 hybrid
__has 40.95% H 6 character in a s orbital

10. A bonding orbital for C4-H7 with 0.9965 electrons
__has 59.23% C 4 character in a s0.95 p3 hybrid
__has 40.77% H 7 character in a s orbital

15. A lone pair orbital for O1 with 0.9920 electrons

16. A lone pair orbital for O1 with 0.9224 electrons

-With core pairs on: O 1 C 2 C 3 C 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, 7, for C3-H9 with the lone pair acceptor orbital, 17, for C2 is 26.3 kJ/mol.

The interaction of the second lone pair donor orbital, 16, for O1 with the lone pair acceptor orbital, 17, for C2 is 167. 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.

21 ----- 2.421
20 ----- 2.214

19 ----- 1.497

18 ----- 0.499

17 -^--- -3.424

16 -^-v- -8.008

15 -^-v- -8.307

14 -^-v- -8.745

13 -^-v- -9.451

12 -^-v- -9.729

11 -^-v- -10.64

10 -^-v- -11.44

9 -^-v- -12.30

8 -^-v- -14.95

7 -^-v- -16.39

6 -^-v- -19.23

5 -^-v- -26.07

4 -^-v- -266.1

3 -^-v- -266.6

2 -^-v- -267.5

1 -^-v- -507.2

## 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 = -193.7625984303 Hartrees