AlH3+

H3
/
AL1 - H2
\
H4
The ion charge is 1. The multiplicity is 2.

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= 1.045
H2 charge= 0.332
H3 charge=-0.188
H4 charge=-0.189
with a dipole moment of 0.53214 Debye

Bond Lengths:

between AL1 and H2: distance=1.670 ang___ between AL1 and H3: distance=1.691 ang___
between AL1 and H4: distance=1.691 ang___ between H2 and H3: distance=1.180 ang___
between H2 and H4: distance=1.182 ang___ between H3 and H4: distance=2.225 ang___

Bond Angles:

for H3-AL1-H2: angle=41.10 deg___ for H4-AL1-H2: angle=41.17 deg___

Top of page.

Bond Orders (Mulliken):

between AL1 and H2: order=0.385___ between AL1 and H3: order=0.593___
between AL1 and H4: order=0.595___ between H2 and H3: order=0.268___
between H2 and H4: order=0.266___ between H3 and H4: order=0.082___

Top of page.

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.

The Lewis structure is built for the up and down electrons, separately. Note that the up and down structures can be very different.

Hybridization in the Best Lewis Structure

Down Electrons

1. A bonding orbital for Al1-H3 with 0.7693 electrons
__has 21.92% Al 1 character in a s0.54 p3 d0.07 hybrid
__has 78.08% H 3 character in a s orbital

2. A bonding orbital for Al1-H4 with 0.7702 electrons
__has 21.94% Al 1 character in a s0.55 p3 d0.07 hybrid
__has 78.06% H 4 character in a s orbital

8. A lone pair orbital for Al1 with 0.9646 electrons
__made from a sp0.42 hybrid

10. A lone pair orbital for H2 with 0.4844 electrons
__made from a s orbital

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

Up Electrons

1. A bonding orbital for Al1-H3 with 0.8096 electrons
__has 19.64% Al 1 character in a sp1.88 d0.09 hybrid
__has 80.36% H 3 character in a s orbital

2. A bonding orbital for Al1-H4 with 0.8108 electrons
__has 19.70% Al 1 character in a sp1.86 d0.09 hybrid
__has 80.30% H 4 character in a s orbital

10. A lone pair orbital for H2 with 0.3602 electrons
__made from a s orbital

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

Top of page.

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, 1, for Al1-H3 with the antibonding acceptor orbital, 49, for Al1-H4 is 21.1 kJ/mol.

The interaction of bonding donor orbital, 2, for Al1-H4 with the antibonding acceptor orbital, 48, for Al1-H3 is 21.0 kJ/mol.

The interaction of bonding donor orbital, 1, for Al1-H3 with the lone pair acceptor orbital, 10, for H2 is 818. kJ/mol.

The interaction of bonding donor orbital, 2, for Al1-H4 with the lone pair acceptor orbital, 10, for H2 is 811. kJ/mol.

The interaction of lone pair donor orbital, 10, for H2 with the lone pair acceptor orbital, 8, for Al1 is 17.0 kJ/mol.

Top of page.

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. Only the spin up electron orbital energies are given.

12 ----- -4.654


11 ----- -6.906

10 ----- -7.018


9 ----- -9.783


8 -^--- -13.62

7 -^-v- -14.07


6 -^-v- -20.35


5 -^-v- -77.92
4 -^-v- -78.02

3 -^-v- -78.25


2 -^-v- -115.2


1 -^-v- -1509.

Top of page.

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 = -243.8261070746 Hartrees

Top of page.

-> Return to Molecular Structure Page. -> Return to Chemistry Home Page