Al(OH)3, Aluminum hydroxide

H7O3 - H4
\ /
O1 - AL2
\
O5
/
H6
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

O1 charge=-0.945
AL2 charge= 1.447
O3 charge=-0.935
H4 charge= 0.462
O5 charge=-0.970
H6 charge= 0.476
H7 charge= 0.465
with a dipole moment of 0.35677 Debye

Bond Lengths:

between O1 and AL2: distance=1.728 ang___ between O1 and O3: distance=3.071 ang___
between O1 and O5: distance=2.970 ang___ between O1 and H7: distance=0.969 ang___
between AL2 and O3: distance=1.733 ang___ between AL2 and O5: distance=1.717 ang___
between O3 and H4: distance=0.974 ang___ between O3 and O5: distance=2.924 ang___
between O5 and H6: distance=0.971 ang___

Bond Angles:

for O3-AL2-O1: angle=125.0 deg___ for H4-O3-AL2: angle=115.3 deg___
for O5-AL2-O1: angle=119.1 deg___ for H6-O5-AL2: angle=123.7 deg___
for H7-O1-AL2: angle=122.4 deg___

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Bond Orders (Mulliken):

between O1 and AL2: order=0.958___ between O1 and O3: order=-0.064___
between O1 and O5: order=-0.067___ between O1 and H7: order=0.860___
between AL2 and O3: order=0.956___ between AL2 and O5: order=0.953___
between O3 and H4: order=0.861___ between O3 and O5: order=-0.066___
between O5 and H6: order=0.857___

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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 O1-Al2 with 1.9926 electrons
__has 90.92% O 1 character in a sp1.46 hybrid
__has 9.08% Al 2 character in a sp1.95 hybrid

2. A bonding orbital for O1-H7 with 1.9941 electrons
__has 74.80% O 1 character in a s0.96 p3 hybrid
__has 25.20% H 7 character in a s orbital

3. A bonding orbital for Al2-O3 with 1.9920 electrons
__has 9.14% Al 2 character in a sp1.93 d0.05 hybrid
__has 90.86% O 3 character in a sp1.54 hybrid

4. A bonding orbital for Al2-O5 with 1.9925 electrons
__has 8.79% Al 2 character in a sp1.99 hybrid
__has 91.21% O 5 character in a sp1.32 hybrid

5. A bonding orbital for O3-H4 with 1.9927 electrons
__has 74.55% O 3 character in a s0.89 p3 hybrid
__has 25.45% H 4 character in a s orbital

6. A bonding orbital for O5-H6 with 1.9943 electrons
__has 74.90% O 5 character in a s0.97 p3 hybrid
__has 25.10% H 6 character in a s orbital

15. A lone pair orbital for O1 with 1.9794 electrons
__made from a sp1.83 hybrid

16. A lone pair orbital for O1 with 1.9536 electrons
__made from a p3 hybrid

17. A lone pair orbital for Al2 with 0.1253 electrons
__made from a p-pi orbital ( 99.99% p)

18. A lone pair orbital for O3 with 1.9823 electrons
__made from a sp1.64 hybrid

19. A lone pair orbital for O3 with 1.9522 electrons
__made from a p-pi orbital ( 99.96% p)

20. A lone pair orbital for O5 with 1.9801 electrons
__made from a sp2.05 hybrid

21. A lone pair orbital for O5 with 1.9530 electrons
__made from a p-pi orbital ( 99.96% p)

-With core pairs on: O 1 Al 2 Al 2 Al 2 Al 2 Al 2 O 3 O 5 -

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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 lone pair donor orbital, 15, for O1 with the antibonding acceptor orbital, 118, for Al2-O3 is 25.8 kJ/mol.

The interaction of the second lone pair donor orbital, 16, for O1 with the lone pair acceptor orbital, 17, for Al2 is 80.3 kJ/mol.

The interaction of lone pair donor orbital, 18, for O3 with the antibonding acceptor orbital, 119, for Al2-O5 is 20.4 kJ/mol.

The interaction of the second lone pair donor orbital, 19, for O3 with the lone pair acceptor orbital, 17, for Al2 is 83.2 kJ/mol.

The interaction of lone pair donor orbital, 20, for O5 with the antibonding acceptor orbital, 116, for O1-Al2 is 24.8 kJ/mol.

The interaction of the second lone pair donor orbital, 21, for O5 with the lone pair acceptor orbital, 17, for Al2 is 83.3 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.

24 ----- 0.452

23 ----- 0.344


22 ----- -0.292


21 ----- -1.669


20 -^-v- -7.429

19 -^-v- -7.545

18 -^-v- -8.149
17 -^-v- -8.182
16 -^-v- -8.218

15 -^-v- -8.376


14 -^-v- -11.94

13 -^-v- -12.10

12 -^-v- -12.83


11 -^-v- -23.86

10 -^-v- -23.97

9 -^-v- -24.24


8 -^-v- -69.15
7 -^-v- -69.17

6 -^-v- -69.54


5 -^-v- -106.5


4 -^-v- -506.1
3 -^-v- -506.2

2 -^-v- -506.3


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 = -470.1917674420 Hartrees

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