## CH3AlH2

 H3 H7 H6 \ | / AL1 - C2 / \ H4 H5
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

AL1 charge= 1.095
C2 charge=-0.916
H3 charge=-0.372
H4 charge=-0.369
H5 charge= 0.183
H6 charge= 0.189
H7 charge= 0.190
with a dipole moment of 0.65910 Debye

## Bond Lengths:

between AL1 and C2: distance=1.981 ang___ between AL1 and H3: distance=1.610 ang___
between AL1 and H4: distance=1.610 ang___ between C2 and H5: distance=1.103 ang___
between C2 and H6: distance=1.105 ang___ between C2 and H7: distance=1.107 ang___

## Bond Angles:

for H3-AL1-C2: angle=119.8 deg___ for H4-AL1-C2: angle=121.2 deg___
for H5-C2-AL1: angle=113.0 deg___ for H6-C2-AL1: angle=111.0 deg___
for H7-C2-AL1: angle=109.7 deg___

## Bond Orders (Mulliken):

between AL1 and C2: order=0.800___ between AL1 and H3: order=0.936___
between AL1 and H4: order=0.943___ between C2 and H5: order=0.950___
between C2 and H6: order=0.952___ between C2 and H7: order=0.950___

## 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 Al1-C2 with 1.9831 electrons
__has 19.37% Al 1 character in a sp1.80 hybrid
__has 80.63% C 2 character in a sp2.41 hybrid

2. A bonding orbital for Al1-H3 with 1.9781 electrons
__has 27.90% Al 1 character in a sp2.07 hybrid
__has 72.10% H 3 character in a s orbital

3. A bonding orbital for Al1-H4 with 1.9779 electrons
__has 27.93% Al 1 character in a sp2.06 hybrid
__has 72.07% H 4 character in a s orbital

4. A bonding orbital for C2-H5 with 1.9963 electrons
__has 60.68% C 2 character in a s0.96 p3 hybrid
__has 39.32% H 5 character in a s orbital

5. A bonding orbital for C2-H6 with 1.9928 electrons
__has 60.64% C 2 character in a s0.92 p3 hybrid
__has 39.36% H 6 character in a s orbital

6. A bonding orbital for C2-H7 with 1.9906 electrons
__has 60.58% C 2 character in a s0.90 p3 hybrid
__has 39.42% H 7 character in a s orbital

-With core pairs on:Al 1 Al 1 Al 1 Al 1 Al 1 C 2 -

#### 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 Al1-H3 with the antibonding acceptor orbital, 80, for Al1-C2 is 27.5 kJ/mol.

The interaction of bonding donor orbital, 2, for Al1-H3 with the antibonding acceptor orbital, 82, for Al1-H4 is 20.4 kJ/mol.

The interaction of bonding donor orbital, 3, for Al1-H4 with the antibonding acceptor orbital, 80, for Al1-C2 is 28.9 kJ/mol.

The interaction of bonding donor orbital, 3, for Al1-H4 with the antibonding acceptor orbital, 81, for Al1-H3 is 20.2 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.

16 ----- 1.614

15 ----- 1.089

14 ----- -0.212

13 ----- -2.302

12 -^-v- -6.843

11 -^-v- -6.964

10 -^-v- -9.523
9 -^-v- -9.571

8 -^-v- -9.834

7 -^-v- -16.51

6 -^-v- -68.57 5 -^-v- -68.58

4 -^-v- -69.07

3 -^-v- -105.9

2 -^-v- -265.6

1 -^-v- -1499.

## 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 = -283.5590816782 Hartrees