CH3COO-, acetate ion

O3
\\
C1 = O2
/
H6 - C4
| \
H7H5
The ion charge is -1.

Tell me about the atomic charges, dipole moment, bond lengths, angles, bond orders,
molecular orbital energies, or total energy.
Tell me about the best Lewis structure.

Atomic Charges and Dipole Moment

C1 charge= 0.883
O2 charge=-0.813
O3 charge=-0.814
C4 charge=-0.437
H5 charge= 0.058
H6 charge= 0.059
H7 charge= 0.063
with a dipole moment of 2.62151 Debye

Bond Lengths:

between C1 and O2: distance=1.272 ang___ between C1 and O3: distance=1.272 ang___
between C1 and C4: distance=1.578 ang___ between C1 and H5: distance=2.228 ang___
between C1 and H6: distance=2.225 ang___ between O2 and O3: distance=2.297 ang___
between C4 and H5: distance=1.105 ang___ between C4 and H6: distance=1.105 ang___
between C4 and H7: distance=1.107 ang___

Bond Angles:

for O3-C1-O2: angle=129.0 deg___ for C4-C1-O2: angle=115.6 deg___
for H5-C4-C1: angle=111.1 deg___ for H6-C4-C1: angle=110.7 deg___
for H7-C4-C1: angle=108.5 deg___

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Bond Orders (Mulliken):

between C1 and O2: order=1.585___ between C1 and O3: order=1.577___
between C1 and C4: order=0.781___ between C1 and H5: order=-0.067___
between C1 and H6: order=-0.060___ between O2 and O3: order=-0.216___
between C4 and H5: order=1.000___ between C4 and H6: order=0.998___
between C4 and H7: order=0.995___

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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 1.9973 electrons
__has 35.69% C 1 character in a sp1.88 hybrid
__has 64.31% O 2 character in a sp1.80 hybrid

2. A bonding orbital for C1-O2 with 1.9937 electrons
__has 19.26% C 1 character in a p3 hybrid
__has 80.74% O 2 character in a p3 hybrid

3. A bonding orbital for C1-O3 with 1.9970 electrons
__has 35.64% C 1 character in a sp1.86 hybrid
__has 64.36% O 3 character in a sp1.81 hybrid

4. A bonding orbital for C1-C4 with 1.9939 electrons
__has 43.93% C 1 character in a sp2.27 hybrid
__has 56.07% C 4 character in a sp2.73 hybrid

5. A bonding orbital for C4-H5 with 1.9938 electrons
__has 58.52% C 4 character in a s0.99 p3 hybrid
__has 41.48% H 5 character in a s orbital

6. A bonding orbital for C4-H6 with 1.9931 electrons
__has 58.53% C 4 character in a s0.98 p3 hybrid
__has 41.47% H 6 character in a s orbital

7. A bonding orbital for C4-H7 with 1.9872 electrons
__has 58.43% C 4 character in a s0.93 p3 hybrid
__has 41.57% H 7 character in a s orbital

12. A lone pair orbital for O2 with 1.9768 electrons
__made from a sp0.55 hybrid

13. A lone pair orbital for O2 with 1.9158 electrons
__made from a p-pi orbital ( 99.93% p 0.06% d)

14. A lone pair orbital for O3 with 1.9769 electrons
__made from a sp0.55 hybrid

15. A lone pair orbital for O3 with 1.9152 electrons
__made from a p-pi orbital ( 99.93% p 0.06% d)

16. A lone pair orbital for O3 with 1.6728 electrons
__made from a p3 hybrid

109. A antibonding orbital for C1-O2 with 0.3236 electrons
__has 80.74% C 1 character in a p3 hybrid
__has 19.26% O 2 character in a p3 hybrid

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

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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 C4-H7 with the second antibonding acceptor orbital, 109, for C1-O2 is 20.2 kJ/mol.

The interaction of lone pair donor orbital, 12, for O2 with the antibonding acceptor orbital, 110, for C1-O3 is 20.7 kJ/mol.

The interaction of the second lone pair donor orbital, 13, for O2 with the antibonding acceptor orbital, 110, for C1-O3 is 99.0 kJ/mol.

The interaction of the second lone pair donor orbital, 13, for O2 with the antibonding acceptor orbital, 111, for C1-C4 is 104. kJ/mol.

The interaction of lone pair donor orbital, 14, for O3 with the antibonding acceptor orbital, 108, for C1-O2 is 20.7 kJ/mol.

The interaction of the second lone pair donor orbital, 15, for O3 with the antibonding acceptor orbital, 108, for C1-O2 is 98.8 kJ/mol.

The interaction of the second lone pair donor orbital, 15, for O3 with the antibonding acceptor orbital, 111, for C1-C4 is 104. kJ/mol.

The interaction of the third lone pair donor orbital, 16, for O3 with the second antibonding acceptor orbital, 109, for C1-O2 is 659. kJ/mol.

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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.

20 ----- 8.186

19 ----- 7.197

18 ----- 6.296

17 ----- 5.659

16 -^-v- 0.447

15 -^-v- 0.158


14 -^-v- -0.351


13 -^-v- -3.208

12 -^-v- -3.702

11 -^-v- -4.602

10 -^-v- -5.131

9 -^-v- -5.405


8 -^-v- -6.596


7 -^-v- -12.33


6 -^-v- -17.29


5 -^-v- -19.44


4 -^-v- -261.1


3 -^-v- -263.0


2 -^-v- -499.2
1 -^-v- -499.2

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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 = -228.6154065398 Hartrees

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