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 O1-C2 with 0.9981 electrons
__has 67.16% O 1 character in a sp2.30 hybrid
__has 32.84% C 2 character in a sp2.49 hybrid
2. A bonding orbital for O1-H7 with 0.9939 electrons
__has 73.80% O 1 character in a s0.85 p3 hybrid
__has 26.20% H 7 character in a s orbital
3. A bonding orbital for C2-O3 with 0.9993 electrons
__has 14.04% C 2 character in a p3 hybrid
__has 85.96% O 3 character in a p3 hybrid
4. A bonding orbital for C2-O3 with 0.9986 electrons
__has 34.91% C 2 character in a sp1.86 hybrid
__has 65.09% O 3 character in a sp1.65 hybrid
5. A bonding orbital for C2-C4 with 0.9973 electrons
__has 48.20% C 2 character in a sp1.73 hybrid
__has 51.80% C 4 character in a sp1.90 hybrid
6. A bonding orbital for C4-H5 with 0.9952 electrons
__has 60.78% C 4 character in a sp2.04 hybrid
__has 39.22% H 5 character in a s orbital
7. A bonding orbital for C4-H6 with 0.9945 electrons
__has 62.04% C 4 character in a sp2.05 hybrid
__has 37.96% H 6 character in a s orbital
12. A lone pair orbital for O1 with 0.9910 electrons
__made from a sp1.09 hybrid
13. A lone pair orbital for O1 with 0.9427 electrons
__made from a p-pi orbital ( 99.93% p 0.07% d)
14. A lone pair orbital for O3 with 0.9906 electrons
__made from a sp0.60 hybrid
15. A lone pair orbital for O3 with 0.9488 electrons
__made from a p3 hybrid
16. A lone pair orbital for C4 with 0.9028 electrons
__made from a p3 hybrid
110. A antibonding orbital for C2-O3 with 0.1479 electrons
__has 85.96% C 2 character in a p3 hybrid
__has 14.04% O 3 character in a p3 hybrid
-With core pairs on: O 1 C 2 O 3 C 4 -
Up Electrons
1. A bonding orbital for O1-C2 with 0.9981 electrons
__has 66.63% O 1 character in a sp2.36 hybrid
__has 33.37% C 2 character in a sp2.64 hybrid
2. A bonding orbital for O1-H7 with 0.9939 electrons
__has 73.90% O 1 character in a s0.85 p3 hybrid
__has 26.10% H 7 character in a s orbital
3. A bonding orbital for C2-O3 with 0.9985 electrons
__has 37.66% C 2 character in a sp1.88 hybrid
__has 62.34% O 3 character in a sp1.62 hybrid
4. A bonding orbital for C2-O3 with 0.9618 electrons
__has 51.30% C 2 character in a p3 hybrid
__has 48.70% O 3 character in a p3 hybrid
5. A bonding orbital for C2-C4 with 0.9973 electrons
__has 53.37% C 2 character in a sp1.62 hybrid
__has 46.63% C 4 character in a sp1.94 hybrid
6. A bonding orbital for C4-H5 with 0.9963 electrons
__has 55.71% C 4 character in a sp2.03 hybrid
__has 44.29% H 5 character in a s orbital
7. A bonding orbital for C4-H6 with 0.9953 electrons
__has 57.10% C 4 character in a sp2.03 hybrid
__has 42.90% H 6 character in a s orbital
12. A lone pair orbital for O1 with 0.9918 electrons
__made from a sp1.07 hybrid
13. A lone pair orbital for O1 with 0.9620 electrons
__made from a p3 hybrid
14. A lone pair orbital for O3 with 0.9900 electrons
__made from a sp0.61 hybrid
15. A lone pair orbital for O3 with 0.9437 electrons
__made from a p3 hybrid
-With core pairs on: O 1 C 2 O 3 C 4 -
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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 second bonding donor orbital, 4, for C2-O3 with
the lone pair acceptor orbital, 16, for C4 is 65.8 kJ/mol.
The interaction of the second lone pair donor orbital, 13, for O1 with
the second antibonding acceptor orbital, 111, for C2-O3 is 69.5 kJ/mol.
The interaction of the second lone pair donor orbital, 15, for O3 with
the antibonding acceptor orbital, 108, for O1-C2 is 89.5 kJ/mol.
The interaction of the second lone pair donor orbital, 15, for O3 with
the antibonding acceptor orbital, 112, for C2-C4 is 42.3 kJ/mol.
The interaction of lone pair donor orbital, 16, for C4 with
the second antibonding acceptor orbital, 111, for C2-O3 is 27.8 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.
20 ----- 2.360
19 ----- 1.669
18 ----- 0.005
17 ----- -0.784
16 -^--- -6.611
15 -^-v- -6.906
14 -^-v- -8.138
13 -^-v- -9.571
12 -^-v- -10.68
11 -^-v- -11.31
10 -^-v- -12.08
9 -^-v- -13.33
8 -^-v- -15.55
7 -^-v- -18.97
6 -^-v- -25.48
5 -^-v- -27.48
4 -^-v- -268.1
3 -^-v- -270.1
2 -^-v- -506.5
1 -^-v- -507.9
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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 = -228.5048296372 Hartrees
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