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.
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 C1-H2 with 0.9975 electrons
__has 63.42% C 1 character in a sp1.70 hybrid
__has 36.58% H 2 character in a s orbital
2. A bonding orbital for C1-Br3 with 0.9979 electrons
__has 49.77% C 1 character in a sp2.88 hybrid
__has 50.23% Br 3 character in a s0.46 p3 hybrid
3. A bonding orbital for C1-H4 with 0.9975 electrons
__has 63.42% C 1 character in a sp1.70 hybrid
__has 36.58% H 4 character in a s orbital
19. A lone pair orbital for C1 with 0.9967 electrons
__made from a p3 hybrid
20. A lone pair orbital for Br3 with 0.9988 electrons
__made from a s0.36 p3 hybrid
21. A lone pair orbital for Br3 with 0.9981 electrons
__made from a sp0.31 hybrid
22. A lone pair orbital for Br3 with 0.9924 electrons
__made from a p-pi orbital ( 99.98% p)
-With core pairs on: C 1 Br 3 Br 3 Br 3 Br 3 Br 3 Br 3 Br 3 Br 3 Br 3 Br 3 Br 3 Br 3 Br 3 Br 3 -
Up Electrons
1. A bonding orbital for C1-H2 with 0.9986 electrons
__has 57.91% C 1 character in a sp1.71 hybrid
__has 42.09% H 2 character in a s orbital
2. A bonding orbital for C1-Br3 with 0.9989 electrons
__has 42.23% C 1 character in a sp2.83 hybrid
__has 57.77% Br 3 character in a s0.58 p3 hybrid
3. A bonding orbital for C1-H4 with 0.9986 electrons
__has 57.91% C 1 character in a sp1.71 hybrid
__has 42.09% H 4 character in a s orbital
20. A lone pair orbital for Br3 with 0.9984 electrons
__made from a sp0.19 hybrid
21. A lone pair orbital for Br3 with 0.9915 electrons
__made from a p-pi orbital ( 99.97% p)
22. A lone pair orbital for Br3 with 0.9393 electrons
__made from a p3 hybrid
-With core pairs on: C 1 Br 3 Br 3 Br 3 Br 3 Br 3 Br 3 Br 3 Br 3 Br 3 Br 3 Br 3 Br 3 Br 3 Br 3 -
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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 the third lone pair donor orbital, 22, for Br3 with
the lone pair acceptor orbital, 19, for C1 is 99.1 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.
Only the spin up electron orbital energies are given.
26 ----- 3.428
25 ----- 3.354
24 ----- 2.292
23 ----- -1.197
22 -^--- -4.999
21 -^-v- -7.222
20 -^-v- -8.449
19 -^-v- -10.45
18 -^-v- -11.47
17 -^-v- -16.12
16 -^-v- -20.73
15 -^-v- -68.76 14 -^-v- -68.77
13 -^-v- -69.00
12 -^-v- -69.06
11 -^-v- -69.14
10 -^-v- -172.0
9 -^-v- -172.0
8 -^-v- -172.4
7 -^-v- -229.4
6 -^-v- -268.1
5 -^-v- -1517.
4 -^-v- -1518.
3 -^-v- -1518.
2 -^-v- -1681.
1 -^-v- -13067
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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 = -2613.2448963390 Hartrees
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