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 B1-B2 with 1.0000 electrons
__has 50.00% B 1 character in a p-pi orbital ( 99.53% p 0.47% d)
__has 50.00% B 2 character in a p-pi orbital ( 99.53% p 0.47% d)
2. A bonding orbital for B1-B2 with 1.0000 electrons
__has 50.00% B 1 character in a p-pi orbital ( 99.53% p 0.47% d)
__has 50.00% B 2 character in a p-pi orbital ( 99.53% p 0.47% d)
5. A lone pair orbital for B1 with 0.8255 electrons
__made from a s orbital
6. A lone pair orbital for B1 with 0.1744 electrons
__made from a p3 hybrid
7. A lone pair orbital for B2 with 0.8255 electrons
__made from a s orbital
8. A lone pair orbital for B2 with 0.1744 electrons
__made from a p3 hybrid
-With core pairs on: B 1 B 2 -
Up Electrons
1. A bonding orbital for B1-B2 with 0.9222 electrons
__has 63.24% B 1 character in a sp0.27 hybrid
__has 36.76% B 2 character in a sp1.44 hybrid
2. A bonding orbital for B1-B2 with 0.9222 electrons
__has 36.76% B 1 character in a s0.79 p3 hybrid
__has 63.24% B 2 character in a sp0.71 hybrid
-With core pairs on: B 1 B 2 -
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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.
Only the spin up electron orbital energies are given.
10 ----- 1.664
9 ----- -1.726 8 ----- -1.726
7 ----- -5.557
6 -^--- -6.107 5 -^--- -6.107
4 -^-v- -7.592
3 -^-v- -13.57
2 -^-v- -177.9
1 -^-v- -177.9
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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 = -49.4167092274 Hartrees
This configuration is not the ground state configuration of B2.
Rather the experimental configuration is
(2 sigmag+)2
(2 sigma*u+)1
(1 piu+)2
(3 sigmag+)1.
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