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-O2 with 0.9982 electrons
__has 32.76% C 1 character in a sp2.63 hybrid
__has 67.24% O 2 character in a sp1.88 hybrid
2. A bonding orbital for C1-C4 with 0.9964 electrons
__has 52.57% C 1 character in a sp1.65 hybrid
__has 47.43% C 4 character in a sp2.77 hybrid
3. A bonding orbital for C1-C8 with 0.9950 electrons
__has 51.70% C 1 character in a sp1.84 hybrid
__has 48.30% C 8 character in a sp1.88 hybrid
4. A bonding orbital for C1-C8 with 0.9944 electrons
__has 28.82% C 1 character in a p3 hybrid
__has 71.18% C 8 character in a p3 hybrid
5. A bonding orbital for O2-H3 with 0.9935 electrons
__has 77.36% O 2 character in a s0.88 p3 hybrid
__has 22.64% H 3 character in a s orbital
6. A bonding orbital for C4-H5 with 0.9856 electrons
__has 62.61% C 4 character in a s0.94 p3 hybrid
__has 37.39% H 5 character in a s orbital
7. A bonding orbital for C4-H6 with 0.9929 electrons
__has 62.69% C 4 character in a sp2.89 hybrid
__has 37.31% H 6 character in a s orbital
8. A bonding orbital for C4-H7 with 0.9857 electrons
__has 62.60% C 4 character in a s0.94 p3 hybrid
__has 37.40% H 7 character in a s orbital
9. A bonding orbital for C8-H9 with 0.9943 electrons
__has 63.45% C 8 character in a sp2.02 hybrid
__has 36.55% H 9 character in a s orbital
10. A bonding orbital for C8-H10 with 0.9937 electrons
__has 62.77% C 8 character in a sp2.07 hybrid
__has 37.23% H10 character in a s orbital
15. A lone pair orbital for O2 with 0.9899 electrons
__made from a sp1.34 hybrid
16. A lone pair orbital for O2 with 0.9307 electrons
__made from a p-pi orbital ( 99.92% p 0.08% d)
-With core pairs on: C 1 O 2 C 4 C 8 -
Up Electrons
1. A bonding orbital for C1-O2 with 0.9982 electrons
__has 33.33% C 1 character in a sp2.63 hybrid
__has 66.67% O 2 character in a sp1.84 hybrid
2. A bonding orbital for C1-O2 with 0.9914 electrons
__has 18.29% C 1 character in a p-pi orbital ( 99.28% p 0.72% d)
__has 81.71% O 2 character in a p-pi orbital ( 99.89% p 0.11% d)
3. A bonding orbital for C1-C4 with 0.9964 electrons
__has 52.02% C 1 character in a sp1.70 hybrid
__has 47.98% C 4 character in a sp2.75 hybrid
4. A bonding orbital for C1-C8 with 0.9948 electrons
__has 54.20% C 1 character in a sp1.80 hybrid
__has 45.80% C 8 character in a sp1.91 hybrid
5. A bonding orbital for O2-H3 with 0.9939 electrons
__has 76.58% O 2 character in a s0.88 p3 hybrid
__has 23.42% H 3 character in a s orbital
6. A bonding orbital for C4-H5 with 0.9807 electrons
__has 63.34% C 4 character in a s0.94 p3 hybrid
__has 36.66% H 5 character in a s orbital
7. A bonding orbital for C4-H6 with 0.9931 electrons
__has 62.72% C 4 character in a sp2.89 hybrid
__has 37.28% H 6 character in a s orbital
8. A bonding orbital for C4-H7 with 0.9808 electrons
__has 63.33% C 4 character in a s0.94 p3 hybrid
__has 36.67% H 7 character in a s orbital
9. A bonding orbital for C8-H9 with 0.9952 electrons
__has 59.55% C 8 character in a sp2.02 hybrid
__has 40.45% H 9 character in a s orbital
10. A bonding orbital for C8-H10 with 0.9946 electrons
__has 58.79% C 8 character in a sp2.06 hybrid
__has 41.21% H10 character in a s orbital
15. A lone pair orbital for O2 with 0.9895 electrons
__made from a sp1.38 hybrid
-With core pairs on: C 1 O 2 C 4 C 8 -
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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 bonding donor orbital, 6, for C4-H5 with
the second antibonding acceptor orbital, 124, for C1-O2 is 23.5 kJ/mol.
The interaction of bonding donor orbital, 8, for C4-H7 with
the second antibonding acceptor orbital, 124, for C1-O2 is 23.3 kJ/mol.
The interaction of the second antibonding donor orbital, 124, for C1-O2 with
the lone pair acceptor orbital, 16, for C8 is 26.9 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 ----- -2.889
19 ----- -3.116
18 ----- -5.254
17 ----- -8.091
16 -^--- -12.96
15 -^-v- -15.28
14 -^-v- -15.49
13 -^-v- -15.52
12 -^-v- -16.68
11 -^-v- -17.74
10 -^-v- -18.16
9 -^-v- -18.90
8 -^-v- -21.88
7 -^-v- -23.90
6 -^-v- -26.20
5 -^-v- -34.11
4 -^-v- -272.4
3 -^-v- -274.0
2 -^-v- -276.0
1 -^-v- -515.0
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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 = -192.8868268876 Hartrees
*This ion results from the McLafferty rearrangment of 2-pentanone
radical cation (propylmethyl ketone radical cation).
The ion, of course, can also be created directly from the enol tautomer
of propanone.
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