## cis-1,2-dibromoethane

 H3 H8 BR7 \ | / H5 - C1 - C2 / \ BR4 H6
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=-0.191
C2 charge=-0.194
H3 charge= 0.151
BR4 charge=-0.121
H5 charge= 0.161
H6 charge= 0.153
BR7 charge=-0.121
H8 charge= 0.162
with a dipole moment of 2.76678 Debye

## Bond Lengths:

between C1 and C2: distance=1.511 ang___ between C1 and H3: distance=1.099 ang___
between C1 and BR4: distance=1.994 ang___ between C1 and H5: distance=1.103 ang___
between C2 and H6: distance=1.099 ang___ between C2 and BR7: distance=1.995 ang___
between C2 and H8: distance=1.103 ang___

## Bond Angles:

for H3-C1-C2: angle=112.8 deg___ for BR4-C1-C2: angle=113.1 deg___
for H5-C1-C2: angle=109.8 deg___ for H6-C2-C1: angle=112.7 deg___
for BR7-C2-C1: angle=113.0 deg___ for H8-C2-C1: angle=110.0 deg___

## Bond Orders (Mulliken):

between C1 and C2: order=1.027___ between C1 and H3: order=0.931___
between C1 and BR4: order=1.065___ between C1 and H5: order=0.906___
between C2 and H6: order=0.931___ between C2 and BR7: order=1.064___
between C2 and H8: order=0.906___

## 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 1.9976 electrons
__has 50.00% C 1 character in a sp2.20 hybrid
__has 50.00% C 2 character in a sp2.20 hybrid

2. A bonding orbital for C1-H3 with 1.9896 electrons
__has 63.16% C 1 character in a sp2.74 hybrid
__has 36.84% H 3 character in a s orbital

3. A bonding orbital for C1-Br4 with 1.9904 electrons
__has 45.91% C 1 character in a s0.58 p3 hybrid
__has 54.09% Br 4 character in a s0.43 p3 hybrid

4. A bonding orbital for C1-H5 with 1.9798 electrons
__has 62.77% C 1 character in a sp2.82 hybrid
__has 37.23% H 5 character in a s orbital

5. A bonding orbital for C2-H6 with 1.9896 electrons
__has 63.15% C 2 character in a sp2.74 hybrid
__has 36.85% H 6 character in a s orbital

6. A bonding orbital for C2-Br7 with 1.9904 electrons
__has 45.88% C 2 character in a s0.58 p3 hybrid
__has 54.12% Br 7 character in a s0.43 p3 hybrid

7. A bonding orbital for C2-H8 with 1.9799 electrons
__has 62.78% C 2 character in a sp2.81 hybrid
__has 37.22% H 8 character in a s orbital

38. A lone pair orbital for Br4 with 1.9974 electrons

39. A lone pair orbital for Br4 with 1.9894 electrons

40. A lone pair orbital for Br4 with 1.9852 electrons

41. A lone pair orbital for Br7 with 1.9974 electrons

42. A lone pair orbital for Br7 with 1.9894 electrons

43. A lone pair orbital for Br7 with 1.9852 electrons

-With core pairs on: C 1 C 2 Br 4 Br 4 Br 4 Br 4 Br 4 Br 4 Br 4 Br 4 Br 4 Br 4 Br 4 Br 4 Br 4 Br 4 Br 7 Br 7 Br 7 Br 7 Br 7 Br 7 Br 7 Br 7 Br 7 Br 7 Br 7 Br 7 Br 7 Br 7 -

#### 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 C1-H5 with the antibonding acceptor orbital, 125, for C2-Br7 is 36.2 kJ/mol.

The interaction of bonding donor orbital, 7, for C2-H8 with the antibonding acceptor orbital, 122, for C1-Br4 is 36.0 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.

47 ----- 1.498
46 ----- 1.393

45 ----- -1.410

44 ----- -1.955

43 -^-v- -6.693

42 -^-v- -6.884

41 -^-v- -7.007
40 -^-v- -7.026

39 -^-v- -9.267

38 -^-v- -9.517

37 -^-v- -10.85

36 -^-v- -11.78

35 -^-v- -12.08

34 -^-v- -15.33

33 -^-v- -17.99

32 -^-v- -19.73

31 -^-v- -21.12

30 -^-v- -68.19 29 -^-v- -68.19 28 -^-v- -68.19 27 -^-v- -68.19

26 -^-v- -68.49 25 -^-v- -68.50 24 -^-v- -68.50 23 -^-v- -68.51

22 -^-v- -68.61 21 -^-v- -68.62

20 -^-v- -171.4 19 -^-v- -171.4 18 -^-v- -171.4 17 -^-v- -171.4

16 -^-v- -171.8 15 -^-v- -171.9

14 -^-v- -228.9 13 -^-v- -228.9

12 -^-v- -268.4 11 -^-v- -268.4

10 -^-v- -1517. 9 -^-v- -1517. 8 -^-v- -1517. 7 -^-v- -1517.
6 -^-v- -1517. 5 -^-v- -1517.

4 -^-v- -1680. 3 -^-v- -1680.

2 -^-v- -13067 1 -^-v- -13067

## 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 = -5226.6300044015 Hartrees