## NF4-

 F3 F5 \ | N1 - F2 | F4
The ion charge is -1.

## Atomic Charges and Dipole Moment

N1 charge= 0.253
F2 charge=-0.091
F3 charge=-0.087
F4 charge=-0.547
F5 charge=-0.527
with a dipole moment of 1.99062 Debye

## Bond Lengths:

between N1 and F2: distance=1.425 ang___ between N1 and F3: distance=1.422 ang___
between N1 and F4: distance=1.928 ang___ between N1 and F5: distance=1.889 ang___
between F4 and F5: distance=3.778 ang___

## Bond Angles:

for F3-N1-F2: angle=101.1 deg___ for F4-N1-F2: angle=95.95 deg___
for F5-N1-F2: angle=95.07 deg___

## Bond Orders (Mulliken):

between N1 and F2: order=0.896___ between N1 and F3: order=0.898___
between N1 and F4: order=0.403___ between N1 and F5: order=0.442___
between F4 and F5: order=0.055___

## 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 N1-F2 with 1.9928 electrons
__has 35.67% N 1 character in a s0.38 p3 hybrid
__has 64.33% F 2 character in a s0.43 p3 hybrid

2. A bonding orbital for N1-F3 with 1.9927 electrons
__has 35.77% N 1 character in a s0.39 p3 hybrid
__has 64.23% F 3 character in a s0.43 p3 hybrid

3. A bonding orbital for N1-F5 with 1.9975 electrons
__has 18.16% N 1 character in a p3 hybrid
__has 81.84% F 5 character in a s0.18 p3 hybrid

9. A lone pair orbital for N1 with 1.9986 electrons

10. A lone pair orbital for F2 with 1.9962 electrons

11. A lone pair orbital for F2 with 1.9768 electrons
__made from a s0.10 p3 hybrid

12. A lone pair orbital for F2 with 1.9585 electrons
__made from a p-pi orbital ( 99.98% p)

13. A lone pair orbital for F3 with 1.9962 electrons

14. A lone pair orbital for F3 with 1.9762 electrons
__made from a s0.09 p3 hybrid

15. A lone pair orbital for F3 with 1.9583 electrons
__made from a p-pi orbital ( 99.98% p)

16. A lone pair orbital for F4 with 1.9993 electrons

17. A lone pair orbital for F4 with 1.9968 electrons
__made from a s0.07 p3 hybrid

18. A lone pair orbital for F4 with 1.9951 electrons

19. A lone pair orbital for F4 with 1.7338 electrons
__made from a s0.17 p3 hybrid

20. A lone pair orbital for F5 with 1.9992 electrons

21. A lone pair orbital for F5 with 1.9965 electrons
__made from a s0.07 p3 hybrid

22. A lone pair orbital for F5 with 1.9947 electrons
__made from a p-pi orbital (100.00% p)

120. A antibonding orbital for N1-F5 with 0.3364 electrons
__has 81.84% N 1 character in a p3 hybrid
__has 18.16% F 5 character in a s0.18 p3 hybrid

-With core pairs on: N 1 F 2 F 3 F 4 F 5 -

#### 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, 11, for F2 with the antibonding acceptor orbital, 119, for N1-F3 is 46.1 kJ/mol.

The interaction of the third lone pair donor orbital, 12, for F2 with the antibonding acceptor orbital, 120, for N1-F5 is 90.5 kJ/mol.

The interaction of the second lone pair donor orbital, 14, for F3 with the antibonding acceptor orbital, 118, for N1-F2 is 47.4 kJ/mol.

The interaction of the third lone pair donor orbital, 15, for F3 with the antibonding acceptor orbital, 120, for N1-F5 is 91.3 kJ/mol.

The interaction of lone pair donor orbital, 16, for F4 with the antibonding acceptor orbital, 120, for N1-F5 is 28.7 kJ/mol.

The interaction of the second lone pair donor orbital, 17, for F4 with the antibonding acceptor orbital, 119, for N1-F3 is 2.30 kJ/mol.

The interaction of the second lone pair donor orbital, 17, for F4 with the antibonding acceptor orbital, 120, for N1-F5 is 2.38 kJ/mol.

The interaction of the third lone pair donor orbital, 18, for F4 with the antibonding acceptor orbital, 118, for N1-F2 is 3.76 kJ/mol.

The interaction of the third lone pair donor orbital, 18, for F4 with the antibonding acceptor orbital, 119, for N1-F3 is 3.05 kJ/mol.

The interaction of 4th lone pair donor orbital, 19, for F4 with the antibonding acceptor orbital, 118, for N1-F2 is 2.67 kJ/mol.

The interaction of 4th lone pair donor orbital, 19, for F4 with the antibonding acceptor orbital, 119, for N1-F3 is 3.30 kJ/mol.

The interaction of 4th lone pair donor orbital, 19, for F4 with the antibonding acceptor orbital, 120, for N1-F5 is 498. 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.

26 ----- 11.67

25 ----- 3.369
24 ----- 3.074

23 ----- 1.192

22 -^-v- -1.557

21 -^-v- -1.997
20 -^-v- -2.039

19 -^-v- -2.231
18 -^-v- -2.327

17 -^-v- -3.756

16 -^-v- -5.238
15 -^-v- -5.265

14 -^-v- -5.743

13 -^-v- -7.949

12 -^-v- -8.068

11 -^-v- -9.864

10 -^-v- -14.84

9 -^-v- -20.33

8 -^-v- -20.61

7 -^-v- -25.19

6 -^-v- -27.34

5 -^-v- -379.2

4 -^-v- -647.8

3 -^-v- -648.0

2 -^-v- -652.2
1 -^-v- -652.2

## 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 = -454.1797108025 Hartrees