propanoic acid, CH3CH2COOH

H11O3
| //
O1 - C2H6H7
\ | /
C4 - C5
/ | \
H10H9H8
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

O1 charge=-0.632
C2 charge= 0.627
O3 charge=-0.528
C4 charge= 0.035
C5 charge=-0.415
H6 charge= 0.120
H7 charge= 0.123
H8 charge= 0.112
H9 charge= 0.053
H10 charge= 0.057
H11 charge= 0.446
with a dipole moment of 1.62540 Debye

Bond Lengths:

between O1 and C2: distance=1.376 ang___ between O1 and O3: distance=2.273 ang___
between O1 and C4: distance=2.394 ang___ between O1 and H11: distance=0.984 ang___
between C2 and O3: distance=1.223 ang___ between C2 and C4: distance=1.517 ang___
between O3 and C4: distance=2.452 ang___ between C4 and C5: distance=1.535 ang___
between C4 and H9: distance=1.108 ang___ between C4 and H10: distance=1.106 ang___
between C5 and H6: distance=1.103 ang___ between C5 and H7: distance=1.102 ang___
between C5 and H8: distance=1.103 ang___

Bond Angles:

for O3-C2-O1: angle=121.7 deg___ for C4-C2-O1: angle=111.5 deg___
for C5-C4-C2: angle=113.6 deg___ for H6-C5-C4: angle=111.1 deg___
for H7-C5-C4: angle=110.9 deg___ for H8-C5-C4: angle=110.4 deg___
for H9-C4-C2: angle=106.3 deg___ for H10-C4-C2: angle=107.9 deg___
for H11-O1-C2: angle=105.7 deg___

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Bond Orders (Mulliken):

between O1 and C2: order=1.130___ between O1 and O3: order=-0.192___
between O1 and C4: order=-0.171___ between O1 and H11: order=0.837___
between C2 and O3: order=1.943___ between C2 and C4: order=0.813___
between O3 and C4: order=-0.068___ between C4 and C5: order=0.761___
between C4 and H9: order=0.977___ between C4 and H10: order=0.992___
between C5 and H6: order=0.985___ between C5 and H7: order=0.982___
between C5 and H8: order=0.991___

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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 O1-C2 with 1.9954 electrons
__has 67.73% O 1 character in a sp2.28 hybrid
__has 32.27% C 2 character in a sp2.58 hybrid

2. A bonding orbital for O1-H11 with 1.9888 electrons
__has 75.07% O 1 character in a s0.85 p3 hybrid
__has 24.93% H11 character in a s orbital

3. A bonding orbital for C2-O3 with 1.9976 electrons
__has 35.47% C 2 character in a sp1.87 hybrid
__has 64.53% O 3 character in a sp1.56 hybrid

4. A bonding orbital for C2-O3 with 1.9940 electrons
__has 26.07% C 2 character in a p3 hybrid
__has 73.93% O 3 character in a p3 hybrid

5. A bonding orbital for C2-C4 with 1.9870 electrons
__has 49.47% C 2 character in a sp1.64 hybrid
__has 50.53% C 4 character in a s0.96 p3 hybrid

6. A bonding orbital for C4-C5 with 1.9914 electrons
__has 52.16% C 4 character in a sp2.30 hybrid
__has 47.84% C 5 character in a sp2.55 hybrid

7. A bonding orbital for C4-H9 with 1.9710 electrons
__has 60.48% C 4 character in a s0.87 p3 hybrid
__has 39.52% H 9 character in a s orbital

8. A bonding orbital for C4-H10 with 1.9767 electrons
__has 60.55% C 4 character in a s0.90 p3 hybrid
__has 39.45% H10 character in a s orbital

9. A bonding orbital for C5-H6 with 1.9920 electrons
__has 59.61% C 5 character in a s0.94 p3 hybrid
__has 40.39% H 6 character in a s orbital

10. A bonding orbital for C5-H7 with 1.9918 electrons
__has 60.07% C 5 character in a s0.95 p3 hybrid
__has 39.93% H 7 character in a s orbital

11. A bonding orbital for C5-H8 with 1.9909 electrons
__has 59.30% C 5 character in a s0.94 p3 hybrid
__has 40.70% H 8 character in a s orbital

17. A lone pair orbital for O1 with 1.9813 electrons
__made from a sp1.10 hybrid

18. A lone pair orbital for O1 with 1.8836 electrons
__made from a p-pi orbital ( 99.94% p 0.06% d)

19. A lone pair orbital for O3 with 1.9772 electrons
__made from a sp0.63 hybrid

20. A lone pair orbital for O3 with 1.8856 electrons
__made from a p3 hybrid

149. A antibonding orbital for C2-O3 with 0.1407 electrons
__has 73.93% C 2 character in a p3 hybrid
__has 26.07% O 3 character in a p3 hybrid

-With core pairs on: O 1 C 2 O 3 C 4 C 5 -

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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, 2, for O1-H11 with the antibonding acceptor orbital, 150, for C2-C4 is 22.7 kJ/mol.

The interaction of bonding donor orbital, 7, for C4-H9 with the second antibonding acceptor orbital, 149, for C2-O3 is 31.9 kJ/mol.

The interaction of bonding donor orbital, 8, for C4-H10 with the second antibonding acceptor orbital, 149, for C2-O3 is 21.7 kJ/mol.

The interaction of lone pair donor orbital, 17, for O1 with the antibonding acceptor orbital, 148, for C2-O3 is 39.9 kJ/mol.

The interaction of the second lone pair donor orbital, 18, for O1 with the second antibonding acceptor orbital, 149, for C2-O3 is 228. kJ/mol.

The interaction of the second lone pair donor orbital, 20, for O3 with the antibonding acceptor orbital, 146, for O1-C2 is 179. kJ/mol.

The interaction of the second lone pair donor orbital, 20, for O3 with the antibonding acceptor orbital, 150, for C2-C4 is 101. 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.

24 ----- 1.931

23 ----- 1.526

22 ----- 0.747


21 ----- -1.385


20 -^-v- -6.680


19 -^-v- -7.959

18 -^-v- -8.528

17 -^-v- -8.955

16 -^-v- -9.504

15 -^-v- -10.03

14 -^-v- -10.28


13 -^-v- -11.72

12 -^-v- -11.92

11 -^-v- -12.34


10 -^-v- -14.47


9 -^-v- -16.70


8 -^-v- -19.51


7 -^-v- -25.25


6 -^-v- -27.55


5 -^-v- -266.2

4 -^-v- -266.9


3 -^-v- -270.0


2 -^-v- -506.4


1 -^-v- -507.8

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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 = -268.5028889484 Hartrees

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