## SiF22+

 F3 = SI1 = F2
The ion charge is 2.

## Atomic Charges and Dipole Moment

SI1 charge= 2.023
F2 charge=-0.011
F3 charge=-0.011
with a dipole moment of 0.01006 Debye

## Bond Lengths:

between SI1 and F2: distance=1.532 ang___ between SI1 and F3: distance=1.532 ang___
between F2 and F3: distance=3.063 ang___

## Bond Angles:

for F3-SI1-F2: angle=179.8 deg___

## Bond Orders (Mulliken):

between SI1 and F2: order=1.469___ between SI1 and F3: order=1.469___
between F2 and F3: order=0.094___

## 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 Si1-F2 with 1.9907 electrons
__has 15.95% Si 1 character in a sp1.01 hybrid
__has 84.05% F 2 character in a s0.54 p3 hybrid

2. A bonding orbital for Si1-F3 with 1.9907 electrons
__has 15.95% Si 1 character in a sp1.01 hybrid
__has 84.05% F 3 character in a s0.54 p3 hybrid

10. A lone pair orbital for Si1 with 0.1103 electrons
__made from a p-pi orbital (100.00% p)

11. A lone pair orbital for Si1 with 0.1103 electrons
__made from a p-pi orbital (100.00% p)

12. A lone pair orbital for F2 with 1.9884 electrons

13. A lone pair orbital for F2 with 1.9331 electrons
__made from a p-pi orbital ( 99.91% p 0.09% d)

14. A lone pair orbital for F2 with 1.9331 electrons
__made from a p-pi orbital ( 99.91% p 0.09% d)

15. A lone pair orbital for F3 with 1.9884 electrons

16. A lone pair orbital for F3 with 1.9332 electrons
__made from a p-pi orbital ( 99.91% p 0.09% d)

17. A lone pair orbital for F3 with 1.9332 electrons
__made from a p-pi orbital ( 99.91% p 0.09% d)

-With core pairs on:Si 1 Si 1 Si 1 Si 1 Si 1 F 2 F 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, 13, for F2 with the lone pair acceptor orbital, 10, for Si1 is 122. kJ/mol.

The interaction of the third lone pair donor orbital, 14, for F2 with the second lone pair acceptor orbital, 11, for Si1 is 122. kJ/mol.

The interaction of the second lone pair donor orbital, 16, for F3 with the lone pair acceptor orbital, 10, for Si1 is 122. kJ/mol.

The interaction of the third lone pair donor orbital, 17, for F3 with the second lone pair acceptor orbital, 11, for Si1 is 122. 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.

19 ----- -10.76

18 ----- -18.97 17 ----- -18.97

16 ----- -22.54

15 -^-v- -27.72 14 -^-v- -27.72

13 -^-v- -28.14 12 -^-v- -28.14

11 -^-v- -29.58

10 -^-v- -31.01

9 -^-v- -47.35

8 -^-v- -47.67

7 -^-v- -116.5

6 -^-v- -117.1 5 -^-v- -117.1

4 -^-v- -159.3

3 -^-v- -674.1 2 -^-v- -674.1

1 -^-v- -1795.

## 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 = -488.2732300115 Hartrees