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-O2 with 1.9917 electrons
__has 8.90% Al 1 character in a sp2.25 d0.05 hybrid
__has 91.10% O 2 character in a sp1.08 hybrid
2. A bonding orbital for Al1-H3 with 1.9784 electrons
__has 27.65% Al 1 character in a sp1.75 hybrid
__has 72.35% H 3 character in a s orbital
3. A bonding orbital for Al1-H4 with 1.9746 electrons
__has 26.99% Al 1 character in a sp1.91 d0.05 hybrid
__has 73.01% H 4 character in a s orbital
4. A bonding orbital for O2-H5 with 1.9956 electrons
__has 74.37% O 2 character in a s0.80 p3 hybrid
__has 25.63% H 5 character in a s orbital
12. A lone pair orbital for O2 with 1.9857 electrons
__made from a sp2.20 hybrid
13. A lone pair orbital for O2 with 1.9424 electrons
__made from a p3 hybrid
-With core pairs on:Al 1 Al 1 Al 1 Al 1 Al 1 O 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, 70, for Al1-O2 is 21.7 kJ/mol.
The interaction of bonding donor orbital, 2, for Al1-H3 with
the antibonding acceptor orbital, 72, for Al1-H4 is 22.3 kJ/mol.
The interaction of bonding donor orbital, 3, for Al1-H4 with
the antibonding acceptor orbital, 70, for Al1-O2 is 37.1 kJ/mol.
The interaction of bonding donor orbital, 3, for Al1-H4 with
the antibonding acceptor orbital, 71, for Al1-H3 is 21.7 kJ/mol.
The interaction of the second lone pair donor orbital, 13, for O2 with
the lone pair acceptor orbital, 11, for Al1 is 105. 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.
16 ----- 1.568
15 ----- 0.649
14 ----- -0.758
13 ----- -2.018
12 -^-v- -7.103
11 -^-v- -7.709
10 -^-v- -8.046
9 -^-v- -9.530
8 -^-v- -12.30
7 -^-v- -23.92
6 -^-v- -68.91
5 -^-v- -68.98
4 -^-v- -69.36
3 -^-v- -106.3
2 -^-v- -506.1
1 -^-v- -1500.
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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 = -319.5441891648 Hartrees
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