## trans-difluoroethylene, CHF=CHF

 F3 H6 \ / C1 = C2 / \ H4 F5
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

C1 charge=-0.056
C2 charge=-0.061
F3 charge=-0.144
H4 charge= 0.201
F5 charge=-0.143
H6 charge= 0.203
with a dipole moment of 0 Debye

## Bond Lengths:

between C1 and C2: distance=1.337 ang___ between C1 and F3: distance=1.366 ang___
between C1 and H4: distance=1.094 ang___ between C2 and F5: distance=1.366 ang___
between C2 and H6: distance=1.094 ang___

## Bond Angles:

for F3-C1-C2: angle=119.7 deg___ for H4-C1-C2: angle=125.8 deg___
for F5-C2-C1: angle=119.7 deg___ for H6-C2-C1: angle=125.8 deg___

## Bond Orders (Mulliken):

between C1 and C2: order=1.920___ between C1 and F3: order=0.826___
between C1 and H4: order=0.989___ between C2 and F5: order=0.826___
between C2 and H6: order=0.989___

## 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 C1-C2 with 1.9969 electrons
__has 50.00% C 1 character in a sp1.42 hybrid
__has 50.00% C 2 character in a sp1.42 hybrid

2. A bonding orbital for C1-C2 with 1.9957 electrons
__has 50.00% C 1 character in a p-pi orbital ( 99.79% p 0.21% d)
__has 50.00% C 2 character in a p-pi orbital ( 99.79% p 0.21% d)

3. A bonding orbital for C1-F3 with 1.9957 electrons
__has 28.03% C 1 character in a s0.98 p3 hybrid
__has 71.97% F 3 character in a sp2.63 hybrid

4. A bonding orbital for C1-H4 with 1.9879 electrons
__has 59.49% C 1 character in a sp1.91 hybrid
__has 40.51% H 4 character in a s orbital

5. A bonding orbital for C2-F5 with 1.9957 electrons
__has 28.03% C 2 character in a s0.98 p3 hybrid
__has 71.97% F 5 character in a sp2.63 hybrid

6. A bonding orbital for C2-H6 with 1.9879 electrons
__has 59.49% C 2 character in a sp1.91 hybrid
__has 40.51% H 6 character in a s orbital

11. A lone pair orbital for F3 with 1.9937 electrons

12. A lone pair orbital for F3 with 1.9760 electrons

13. A lone pair orbital for F3 with 1.9573 electrons
__made from a p-pi orbital ( 99.98% p)

14. A lone pair orbital for F5 with 1.9937 electrons

15. A lone pair orbital for F5 with 1.9760 electrons

16. A lone pair orbital for F5 with 1.9573 electrons
__made from a p-pi orbital ( 99.98% p)

-With core pairs on: C 1 C 2 F 3 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, 12, for F3 with the antibonding acceptor orbital, 103, for C1-C2 is 32.0 kJ/mol.

The interaction of the second lone pair donor orbital, 12, for F3 with the antibonding acceptor orbital, 106, for C1-H4 is 34.1 kJ/mol.

The interaction of the third lone pair donor orbital, 13, for F3 with the second antibonding acceptor orbital, 104, for C1-C2 is 93.0 kJ/mol.

The interaction of the second lone pair donor orbital, 15, for F5 with the antibonding acceptor orbital, 103, for C1-C2 is 32.0 kJ/mol.

The interaction of the second lone pair donor orbital, 15, for F5 with the antibonding acceptor orbital, 108, for C2-H6 is 34.1 kJ/mol.

The interaction of the third lone pair donor orbital, 16, for F5 with the second antibonding acceptor orbital, 104, for C1-C2 is 93.0 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 ----- 2.493

19 ----- 1.717

18 ----- -0.302

17 ----- -1.306

16 -^-v- -6.559

15 -^-v- -9.133

14 -^-v- -9.941

13 -^-v- -11.02

12 -^-v- -11.75

11 -^-v- -12.06

10 -^-v- -13.52

9 -^-v- -13.87

8 -^-v- -15.59

7 -^-v- -19.35

6 -^-v- -30.63

5 -^-v- -30.73

4 -^-v- -268.9
3 -^-v- -268.9

2 -^-v- -656.4 1 -^-v- -656.4

## 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 = -277.1634870190 Hartrees