BH3, dimerizes to form diborane

H3
\
B1 - H2
/
H4
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

B1 charge= 0.479
H2 charge=-0.160
H3 charge=-0.159
H4 charge=-0.159
with a dipole moment of 0.00282 Debye

Bond Lengths:

between B1 and H2: distance=1.205 ang___ between B1 and H3: distance=1.205 ang___
between B1 and H4: distance=1.205 ang___

Bond Angles:

for H3-B1-H2: angle=120.0 deg___ for H4-B1-H2: angle=119.9 deg___

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Bond Orders (Mulliken):

between B1 and H2: order=0.991___ between B1 and H3: order=0.991___
between B1 and H4: order=0.991___

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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 B1-H2 with 1.9970 electrons
__has 43.20% B 1 character in a sp1.99 hybrid
__has 56.80% H 2 character in a s orbital

2. A bonding orbital for B1-H3 with 1.9970 electrons
__has 43.20% B 1 character in a sp1.99 hybrid
__has 56.80% H 3 character in a s orbital

3. A bonding orbital for B1-H4 with 1.9970 electrons
__has 43.20% B 1 character in a sp1.99 hybrid
__has 56.80% H 4 character in a s orbital

-With core pairs on: B 1 -

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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.

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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.

8 ----- 3.265

7 ----- 2.188 6 ----- 2.185


5 ----- -3.374


4 -^-v- -8.461 3 -^-v- -8.463


2 -^-v- -12.53


1 -^-v- -175.6

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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 = -26.6039022936 Hartrees

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