AlH3NH3 Lewis Acid-Base Complex

H3H8H7
| | /
H5 - AL1 - N2
| \
H4H6
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= 0.843
N2 charge=-0.763
H3 charge=-0.357
H4 charge=-0.356
H5 charge=-0.356
H6 charge= 0.329
H7 charge= 0.329
H8 charge= 0.330
with a dipole moment of 5.45071 Debye

Bond Lengths:

between AL1 and N2: distance=2.105 ang___ between AL1 and H3: distance=1.622 ang___
between AL1 and H4: distance=1.622 ang___ between AL1 and H5: distance=1.622 ang___
between N2 and H6: distance=1.028 ang___ between N2 and H7: distance=1.028 ang___
between N2 and H8: distance=1.027 ang___

Bond Angles:

for H3-AL1-N2: angle=98.87 deg___ for H4-AL1-N2: angle=99.12 deg___
for H5-AL1-N2: angle=98.70 deg___ for H6-N2-AL1: angle=110.9 deg___
for H7-N2-AL1: angle=111.0 deg___ for H8-N2-AL1: angle=110.6 deg___

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Bond Orders (Mulliken):

between AL1 and N2: order=0.313___ between AL1 and H3: order=0.873___
between AL1 and H4: order=0.873___ between AL1 and H5: order=0.873___
between N2 and H6: order=0.885___ between N2 and H7: order=0.885___
between N2 and H8: order=0.885___

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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-N2 with 1.9820 electrons
__has 7.60% Al 1 character in a s0.48 p3 hybrid
__has 92.40% N 2 character in a sp1.64 hybrid

2. A bonding orbital for Al1-H3 with 1.9808 electrons
__has 28.57% Al 1 character in a sp2.44 hybrid
__has 71.43% H 3 character in a s orbital

3. A bonding orbital for Al1-H4 with 1.9809 electrons
__has 28.58% Al 1 character in a sp2.43 hybrid
__has 71.42% H 4 character in a s orbital

4. A bonding orbital for Al1-H5 with 1.9808 electrons
__has 28.56% Al 1 character in a sp2.44 hybrid
__has 71.44% H 5 character in a s orbital

5. A bonding orbital for N2-H6 with 1.9981 electrons
__has 70.20% N 2 character in a s0.78 p3 hybrid
__has 29.80% H 6 character in a s orbital

6. A bonding orbital for N2-H7 with 1.9981 electrons
__has 70.20% N 2 character in a s0.78 p3 hybrid
__has 29.80% H 7 character in a s orbital

7. A bonding orbital for N2-H8 with 1.9980 electrons
__has 70.20% N 2 character in a s0.78 p3 hybrid
__has 29.80% H 8 character in a s orbital

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

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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, 85, for Al1-N2 is 25.4 kJ/mol.

The interaction of bonding donor orbital, 3, for Al1-H4 with the antibonding acceptor orbital, 85, for Al1-N2 is 25.3 kJ/mol.

The interaction of bonding donor orbital, 4, for Al1-H5 with the antibonding acceptor orbital, 85, for Al1-N2 is 25.4 kJ/mol.

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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.

17 ----- 1.202

16 ----- 1.057 15 ----- 1.054


14 ----- -1.119


13 -^-v- -6.141 12 -^-v- -6.143


11 -^-v- -7.977


10 -^-v- -10.76


9 -^-v- -13.53
8 -^-v- -13.54


7 -^-v- -23.28


6 -^-v- -67.42 5 -^-v- -67.43

4 -^-v- -67.71


3 -^-v- -104.7


2 -^-v- -379.1


1 -^-v- -1498.

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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 = -300.8427536943 Hartrees

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