## C2H4O2, HOCH2-CH=O, hydroxylacetaldehyde

 O4 \\ H8 C3 - H5 | / O1 - C2 | \ H6 H7
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=-0.578
C2 charge= 0.188
C3 charge= 0.305
O4 charge=-0.406
H5 charge= 0.026
H6 charge= 0.046
H7 charge= 0.046
H8 charge= 0.370
with a dipole moment of 2.71702 Debye

## Bond Lengths:

between O1 and C2: distance=1.414 ang___ between O1 and H8: distance=0.987 ang___
between C2 and C3: distance=1.510 ang___ between C2 and O4: distance=2.388 ang___
between C2 and H6: distance=1.114 ang___ between C2 and H7: distance=1.115 ang___
between C3 and O4: distance=1.229 ang___ between C3 and H5: distance=1.119 ang___

## Bond Angles:

for C3-C2-O1: angle=112.3 deg___ for O4-C3-C2: angle=121.0 deg___
for H5-C3-O4: angle=121.5 deg___ for H6-C2-O1: angle=111.3 deg___
for H7-C2-O1: angle=111.3 deg___ for H8-O1-C2: angle=104.9 deg___

## Bond Orders (Mulliken):

between O1 and C2: order=0.937___ between O1 and H8: order=0.840___
between C2 and C3: order=0.831___ between C2 and O4: order=-0.062___
between C2 and H6: order=0.966___ between C2 and H7: order=0.959___
between C3 and O4: order=1.916___ between C3 and H5: order=0.956___

## 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.

### Hybridization in the Best Lewis Structure

1. A bonding orbital for O1-C2 with 1.9967 electrons
__has 64.31% O 1 character in a sp2.57 hybrid
__has 35.69% C 2 character in a sp2.95 hybrid

2. A bonding orbital for O1-H8 with 1.9892 electrons
__has 75.10% O 1 character in a s0.82 p3 hybrid
__has 24.90% H 8 character in a s orbital

3. A bonding orbital for C2-C3 with 1.9925 electrons
__has 51.09% C 2 character in a sp2.71 hybrid
__has 48.91% C 3 character in a sp1.83 hybrid

4. A bonding orbital for C2-H6 with 1.9744 electrons
__has 58.87% C 2 character in a s0.95 p3 hybrid
__has 41.13% H 6 character in a s orbital

5. A bonding orbital for C2-H7 with 1.9736 electrons
__has 58.84% C 2 character in a s0.94 p3 hybrid
__has 41.16% H 7 character in a s orbital

6. A bonding orbital for C3-O4 with 1.9980 electrons
__has 35.12% C 3 character in a sp1.98 hybrid
__has 64.88% O 4 character in a sp1.52 hybrid

7. A bonding orbital for C3-O4 with 1.9943 electrons
__has 29.48% C 3 character in a p-pi orbital ( 99.39% p 0.61% d)
__has 70.52% O 4 character in a p-pi orbital ( 99.82% p 0.18% d)

8. A bonding orbital for C3-H5 with 1.9894 electrons
__has 57.31% C 3 character in a sp2.14 hybrid
__has 42.69% H 5 character in a s orbital

13. A lone pair orbital for O1 with 1.9837 electrons

14. A lone pair orbital for O1 with 1.9622 electrons
__made from a p-pi orbital ( 99.95% p)

15. A lone pair orbital for O4 with 1.9845 electrons

16. A lone pair orbital for O4 with 1.9066 electrons

-With core pairs on: O 1 C 2 C 3 O 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, 4, for C2-H6 with the second antibonding acceptor orbital, 119, for C3-O4 is 30.6 kJ/mol.

The interaction of bonding donor orbital, 5, for C2-H7 with the second antibonding acceptor orbital, 119, for C3-O4 is 31.7 kJ/mol.

The interaction of the second lone pair donor orbital, 14, for O1 with the antibonding acceptor orbital, 116, for C2-H6 is 39.6 kJ/mol.

The interaction of the second lone pair donor orbital, 14, for O1 with the antibonding acceptor orbital, 117, for C2-H7 is 40.3 kJ/mol.

The interaction of the second lone pair donor orbital, 16, for O4 with the antibonding acceptor orbital, 115, for C2-C3 is 100. kJ/mol.

The interaction of the second lone pair donor orbital, 16, for O4 with the antibonding acceptor orbital, 120, for C3-H5 is 115. 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.

20 ----- 1.933
19 ----- 1.745

18 ----- 0.631

17 ----- -2.768

16 -^-v- -6.756
15 -^-v- -6.782

14 -^-v- -8.815

13 -^-v- -9.834

12 -^-v- -10.70

11 -^-v- -12.02
10 -^-v- -12.12

9 -^-v- -13.14

8 -^-v- -14.80

7 -^-v- -18.44

6 -^-v- -25.51

5 -^-v- -26.82

4 -^-v- -268.3

3 -^-v- -269.3

2 -^-v- -506.7

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 = -229.1347829336 Hartrees