## methylacetate radical cation, CH3COOCH3+• (*see note)

 H10 | C8 - H11 O3 / \ // H9 O1 - C2 \ H7 - C4 - H6 | H5
The ion charge is 1. The multiplicity is 2.

## Atomic Charges and Dipole Moment

O1 charge=-0.203
C2 charge= 0.696
O3 charge=-0.105
C4 charge=-0.668
H5 charge= 0.298
H6 charge= 0.303
H7 charge= 0.297
C8 charge=-0.188
H9 charge= 0.206
H10 charge= 0.181
H11 charge= 0.182
with a dipole moment of 4.22651 Debye

## Bond Lengths:

between O1 and C2: distance=1.294 ang___ between O1 and C8: distance=1.506 ang___
between C2 and O3: distance=1.256 ang___ between C2 and C4: distance=1.515 ang___
between C4 and H5: distance=1.111 ang___ between C4 and H6: distance=1.107 ang___
between C4 and H7: distance=1.111 ang___ between C8 and H9: distance=1.097 ang___
between C8 and H10: distance=1.100 ang___ between C8 and H11: distance=1.100 ang___

## Bond Angles:

for O3-C2-O1: angle=126.4 deg___ for C4-C2-O1: angle=120.5 deg___
for H5-C4-C2: angle=105.8 deg___ for H6-C4-C2: angle=113.6 deg___
for H7-C4-C2: angle=105.7 deg___ for C8-O1-C2: angle=119.4 deg___
for H9-C8-O1: angle=103.3 deg___ for H10-C8-O1: angle=108.5 deg___
for H11-C8-O1: angle=108.3 deg___

## Bond Orders (Mulliken):

between O1 and C2: order=1.414___ between O1 and C8: order=0.681___
between C2 and O3: order=1.404___ between C2 and C4: order=0.946___
between C4 and H5: order=0.922___ between C4 and H6: order=0.951___
between C4 and H7: order=0.920___ between C8 and H9: order=0.950___
between C8 and H10: order=0.959___ between C8 and H11: order=0.958___

## 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. (These calculations were done without diffuse functions because of space limitations.)

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 0.9982 electrons
__has 65.94% O 1 character in a sp2.07 hybrid
__has 34.06% C 2 character in a sp2.03 hybrid

2. A bonding orbital for O1-C8 with 0.9917 electrons
__has 73.27% O 1 character in a sp2.57 hybrid
__has 26.73% C 8 character in a s0.71 p3 hybrid

3. A bonding orbital for C2-O3 with 0.9990 electrons
__has 33.06% C 2 character in a sp2.35 hybrid
__has 66.94% O 3 character in a sp2.09 hybrid

4. A bonding orbital for C2-C4 with 0.9943 electrons
__has 52.44% C 2 character in a sp1.65 hybrid
__has 47.56% C 4 character in a s0.90 p3 hybrid

5. A bonding orbital for C4-H5 with 0.9866 electrons
__has 63.22% C 4 character in a sp2.96 hybrid
__has 36.78% H 5 character in a s orbital

6. A bonding orbital for C4-H6 with 0.9947 electrons
__has 63.04% C 4 character in a sp2.75 hybrid
__has 36.96% H 6 character in a s orbital

7. A bonding orbital for C4-H7 with 0.9860 electrons
__has 63.24% C 4 character in a sp2.96 hybrid
__has 36.76% H 7 character in a s orbital

8. A bonding orbital for C8-H9 with 0.9965 electrons
__has 61.63% C 8 character in a sp2.67 hybrid
__has 38.37% H 9 character in a s orbital

9. A bonding orbital for C8-H10 with 0.9966 electrons
__has 60.12% C 8 character in a sp2.72 hybrid
__has 39.88% H10 character in a s orbital

10. A bonding orbital for C8-H11 with 0.9966 electrons
__has 60.17% C 8 character in a sp2.72 hybrid
__has 39.83% H11 character in a s orbital

16. A lone pair orbital for O1 with 0.9795 electrons

17. A lone pair orbital for O1 with 0.8715 electrons
__made from a p-pi orbital ( 99.90% p 0.10% d)

18. A lone pair orbital for C2 with 0.2509 electrons
__made from a p-pi orbital ( 99.84% p 0.16% d)

19. A lone pair orbital for O3 with 0.9921 electrons

20. A lone pair orbital for O3 with 0.9757 electrons

21. A lone pair orbital for O3 with 0.8917 electrons
__made from a p-pi orbital ( 99.86% p 0.14% d)

-With core pairs on: O 1 C 2 O 3 C 4 C 8 -

#### Up Electrons

1. A bonding orbital for O1-C2 with 0.9932 electrons
__has 63.41% O 1 character in a sp2.38 hybrid
__has 36.59% C 2 character in a sp1.93 hybrid

2. A bonding orbital for O1-C8 with 0.9920 electrons
__has 73.21% O 1 character in a sp2.56 hybrid
__has 26.79% C 8 character in a s0.72 p3 hybrid

3. A bonding orbital for C2-O3 with 0.9987 electrons
__has 36.62% C 2 character in a sp2.36 hybrid
__has 63.38% O 3 character in a sp1.83 hybrid

4. A bonding orbital for C2-C4 with 0.9691 electrons
__has 56.41% C 2 character in a sp1.73 hybrid
__has 43.59% C 4 character in a s0.86 p3 hybrid

5. A bonding orbital for C4-H5 with 0.9827 electrons
__has 63.25% C 4 character in a sp2.88 hybrid
__has 36.75% H 5 character in a s orbital

6. A bonding orbital for C4-H6 with 0.9912 electrons
__has 62.73% C 4 character in a sp2.79 hybrid
__has 37.27% H 6 character in a s orbital

7. A bonding orbital for C4-H7 with 0.9824 electrons
__has 63.21% C 4 character in a sp2.89 hybrid
__has 36.79% H 7 character in a s orbital

8. A bonding orbital for C8-H9 with 0.9963 electrons
__has 61.59% C 8 character in a sp2.66 hybrid
__has 38.41% H 9 character in a s orbital

9. A bonding orbital for C8-H10 with 0.9962 electrons
__has 60.08% C 8 character in a sp2.72 hybrid
__has 39.92% H10 character in a s orbital

10. A bonding orbital for C8-H11 with 0.9963 electrons
__has 60.13% C 8 character in a sp2.72 hybrid
__has 39.87% H11 character in a s orbital

16. A lone pair orbital for O1 with 0.9780 electrons

17. A lone pair orbital for O1 with 0.8800 electrons
__made from a p-pi orbital ( 99.91% p 0.09% d)

18. A lone pair orbital for C2 with 0.2853 electrons
__made from a p-pi orbital ( 99.79% p 0.21% d)

19. A lone pair orbital for O3 with 0.9913 electrons

20. A lone pair orbital for O3 with 0.8463 electrons
__made from a p-pi orbital ( 99.85% p 0.15% d)

-With core pairs on: O 1 C 2 O 3 C 4 C 8 -

#### 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, 4, for C2-C4 with the third lone pair acceptor orbital, 21, for O3 is 53.5 kJ/mol.

The interaction of bonding donor orbital, 7, for C4-H7 with the lone pair acceptor orbital, 18, for C2 is 20.3 kJ/mol.

The interaction of lone pair donor orbital, 16, for O1 with the antibonding acceptor orbital, 129, for C2-O3 is 35.2 kJ/mol.

The interaction of the second lone pair donor orbital, 17, for O1 with the lone pair acceptor orbital, 18, for C2 is 299. kJ/mol.

The interaction of the second lone pair donor orbital, 20, for O3 with the lone pair acceptor orbital, 18, for C2 is 428. 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.

24 ----- -3.124

23 ----- -3.826

22 ----- -5.311

21 ----- -8.357

20 -^--- -14.38

19 -^-v- -14.78

18 -^-v- -15.12

17 -^-v- -16.10

16 -^-v- -16.21

15 -^-v- -16.73
14 -^-v- -16.74

13 -^-v- -18.97
12 -^-v- -19.02

11 -^-v- -19.61

10 -^-v- -20.37

9 -^-v- -23.78

8 -^-v- -25.63

7 -^-v- -33.26

6 -^-v- -35.35

5 -^-v- -273.4 4 -^-v- -273.4

3 -^-v- -277.4

2 -^-v- -515.1

1 -^-v- -516.0

## 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 = -268.1190252212 Hartrees

* The different conformers are very close in energy. This conformer is the lower energy strucutre at B3LYP. It is not the lowest energy conformer at the PM3 level.