## SeO2, selenium dioxide

 O3 \\ SE1 = O2
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

SE1 charge= 0.654
O2 charge=-0.327
O3 charge=-0.327
with a dipole moment of 2.74666 Debye

## Bond Lengths:

between SE1 and O2: distance=1.664 ang___ between SE1 and O3: distance=1.664 ang___
between O2 and O3: distance=2.807 ang___

## Bond Angles:

for O3-SE1-O2: angle=115.0 deg___

## Bond Orders (Mulliken):

between SE1 and O2: order=1.737___ between SE1 and O3: order=1.737___
between O2 and O3: order=0.148___

## 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 Se1-O2 with 1.9989 electrons
__has 23.15% Se 1 character in a p-pi orbital ( 97.31% p 2.69% d)
__has 76.85% O 2 character in a p-pi orbital ( 99.73% p 0.27% d)

2. A bonding orbital for Se1-O2 with 1.9924 electrons
__has 30.78% Se 1 character in a s0.50 p3 hybrid
__has 69.22% O 2 character in a s0.63 p3 hybrid

3. A bonding orbital for Se1-O3 with 1.9924 electrons
__has 30.79% Se 1 character in a s0.50 p3 hybrid
__has 69.21% O 3 character in a s0.63 p3 hybrid

20. A lone pair orbital for Se1 with 1.9972 electrons

21. A lone pair orbital for O2 with 1.9976 electrons

22. A lone pair orbital for O2 with 1.9325 electrons
__made from a s0.06 p3 hybrid

23. A lone pair orbital for O3 with 1.9976 electrons

24. A lone pair orbital for O3 with 1.9326 electrons
__made from a s0.06 p3 hybrid

25. A lone pair orbital for O3 with 1.6155 electrons
__made from a p-pi orbital ( 99.74% p 0.26% d)

70. A antibonding orbital for Se1-O2 with 0.3424 electrons
__has 76.85% Se 1 character in a p-pi orbital ( 97.31% p 2.69% d)
__has 23.15% O 2 character in a p-pi orbital ( 99.73% p 0.27% d)

-With core pairs on:Se 1 Se 1 Se 1 Se 1 Se 1 Se 1 Se 1 Se 1 Se 1 Se 1 Se 1 Se 1 Se 1 Se 1 O 2 O 3 -

#### 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 the second lone pair donor orbital, 22, for O2 with the antibonding acceptor orbital, 72, for Se1-O3 is 87.2 kJ/mol.

The interaction of the second lone pair donor orbital, 24, for O3 with the second antibonding acceptor orbital, 71, for Se1-O2 is 87.1 kJ/mol.

The interaction of the third lone pair donor orbital, 25, for O3 with the antibonding acceptor orbital, 70, for Se1-O2 is 471. 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.

29 ----- 4.028

28 ----- -0.879

27 ----- -1.609

26 ----- -5.445

25 -^-v- -7.809

24 -^-v- -7.978

23 -^-v- -8.577

22 -^-v- -10.97
21 -^-v- -11.02

20 -^-v- -11.40

19 -^-v- -16.62

18 -^-v- -24.42

17 -^-v- -26.40

16 -^-v- -58.47
15 -^-v- -58.51
14 -^-v- -58.58
13 -^-v- -58.61
12 -^-v- -58.66

11 -^-v- -155.3

10 -^-v- -155.5 9 -^-v- -155.5

8 -^-v- -209.6

7 -^-v- -507.9 6 -^-v- -507.9

5 -^-v- -1408.
4 -^-v- -1408. 3 -^-v- -1408.

2 -^-v- -1565.

1 -^-v- -12285

## 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 = -2551.8511143094 Hartrees