## Be2+...H2C=CH2, ethylene and Be2+ unsymmetrical complex*

 BE3 \ H5 - C1 - C2 - H6 / \ H4 H7
The ion charge is 2.

## Atomic Charges and Dipole Moment

C1 charge=-1.114
C2 charge= 0.527
BE3 charge= 1.424
H4 charge= 0.440
H5 charge= 0.440
H6 charge= 0.141
H7 charge= 0.140
with a dipole moment of 7.17904 Debye

## Bond Lengths:

between C1 and C2: distance=1.416 ang___ between C1 and BE3: distance=1.849 ang___
between C1 and H4: distance=1.118 ang___ between C1 and H5: distance=1.118 ang___
between C2 and BE3: distance=2.674 ang___ between C2 and H6: distance=1.105 ang___
between C2 and H7: distance=1.105 ang___

## Bond Angles:

for BE3-C1-C2: angle=109.2 deg___ for H4-C1-C2: angle=115.9 deg___
for H5-C1-C2: angle=115.9 deg___ for H6-C2-C1: angle=121.3 deg___
for H7-C2-C1: angle=121.3 deg___

## Bond Orders (Mulliken):

between C1 and C2: order=1.131___ between C1 and BE3: order=0.843___
between C1 and H4: order=0.873___ between C1 and H5: order=0.873___
between C2 and BE3: order=0.142___ between C2 and H6: order=0.898___
between C2 and H7: order=0.898___

## 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 C1-C2 with 1.9975 electrons
__has 52.13% C 1 character in a sp1.95 hybrid
__has 47.87% C 2 character in a sp1.61 hybrid

2. A bonding orbital for C1-Be3 with 1.7682 electrons
__has 84.13% C 1 character in a s0.34 p3 hybrid
__has 15.87% Be 3 character in a sp0.13 hybrid

3. A bonding orbital for C1-H4 with 1.9695 electrons
__has 66.07% C 1 character in a sp2.42 hybrid
__has 33.93% H 4 character in a s orbital

4. A bonding orbital for C1-H5 with 1.9695 electrons
__has 66.09% C 1 character in a sp2.41 hybrid
__has 33.91% H 5 character in a s orbital

5. A bonding orbital for C2-H6 with 1.9893 electrons
__has 62.70% C 2 character in a sp2.22 hybrid
__has 37.30% H 6 character in a s orbital

6. A bonding orbital for C2-H7 with 1.9893 electrons
__has 62.70% C 2 character in a sp2.22 hybrid
__has 37.30% H 7 character in a s orbital

10. A lone pair orbital for C2 with 0.2631 electrons

-With core pairs on: C 1 C 2 Be 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 bonding donor orbital, 2, for C1-Be3 with the lone pair acceptor orbital, 10, for C2 is 362. 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.

13 ----- -12.63 12 ----- -12.64

11 ----- -15.07

10 ----- -16.86

9 -^-v- -20.76

8 -^-v- -21.50

7 -^-v- -22.60

6 -^-v- -23.68

5 -^-v- -26.77

4 -^-v- -31.53

3 -^-v- -123.0

2 -^-v- -279.3

1 -^-v- -280.5

## 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 = -92.4653519347 Hartrees