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 0.9907 electrons
__has 61.18% C 1 character in a s0.96 p3 hybrid
__has 38.82% H 2 character in a s orbital
2. A bonding orbital for C1-H3 with 0.9903 electrons
__has 61.19% C 1 character in a s0.95 p3 hybrid
__has 38.81% H 3 character in a s orbital
3. A bonding orbital for C1-H4 with 0.9986 electrons
__has 59.92% C 1 character in a s0.95 p3 hybrid
__has 40.08% H 4 character in a s orbital
4. A bonding orbital for C1-C5 with 0.9975 electrons
__has 56.10% C 1 character in a sp2.59 hybrid
__has 43.90% C 5 character in a sp2.27 hybrid
5. A bonding orbital for C5-O6 with 0.9990 electrons
__has 32.18% C 5 character in a sp2.10 hybrid
__has 67.82% O 6 character in a sp1.43 hybrid
6. A bonding orbital for C5-O6 with 0.9969 electrons
__has 28.41% C 5 character in a p-pi orbital ( 99.37% p 0.63% d)
__has 71.59% O 6 character in a p-pi orbital ( 99.79% p 0.21% d)
10. A lone pair orbital for C5 with 0.9816 electrons
__made from a sp1.54 hybrid
11. A lone pair orbital for O6 with 0.9929 electrons
__made from a sp0.75 hybrid
12. A lone pair orbital for O6 with 0.9730 electrons
__made from a s0.07 p3 hybrid
-With core pairs on: C 1 C 5 O 6 -
Up Electrons
1. A bonding orbital for C1-H2 with 0.9910 electrons
__has 60.55% C 1 character in a s0.94 p3 hybrid
__has 39.45% H 2 character in a s orbital
2. A bonding orbital for C1-H3 with 0.9905 electrons
__has 60.57% C 1 character in a s0.94 p3 hybrid
__has 39.43% H 3 character in a s orbital
3. A bonding orbital for C1-H4 with 0.9904 electrons
__has 62.15% C 1 character in a sp2.50 hybrid
__has 37.85% H 4 character in a s orbital
4. A bonding orbital for C1-C5 with 0.9985 electrons
__has 49.53% C 1 character in a s0.93 p3 hybrid
__has 50.47% C 5 character in a sp0.80 hybrid
5. A bonding orbital for C5-O6 with 0.9993 electrons
__has 33.43% C 5 character in a sp1.28 hybrid
__has 66.57% O 6 character in a sp1.61 hybrid
6. A bonding orbital for C5-O6 with 0.9975 electrons
__has 21.76% C 5 character in a p3 hybrid
__has 78.24% O 6 character in a p3 hybrid
7. A bonding orbital for C5-O6 with 0.9973 electrons
__has 21.36% C 5 character in a p3 hybrid
__has 78.64% O 6 character in a s0.14 p3 hybrid
11. A lone pair orbital for O6 with 0.9911 electrons
__made from a sp0.74 hybrid
-With core pairs on: C 1 C 5 O 6 -
Top of page.
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, 3, for C1-H4 with
the third antibonding acceptor orbital, 90, for C5-O6 is 23.1 kJ/mol.
Top of page.
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.
16 ----- 2.915
15 ----- 2.198
14 ----- 1.741
13 ----- -2.226
12 -^--- -4.358
11 -^-v- -9.340
10 -^-v- -9.720
9 -^-v- -11.39
8 -^-v- -11.44
7 -^-v- -11.49
6 -^-v- -13.38
5 -^-v- -18.92
4 -^-v- -27.07
3 -^-v- -267.2
2 -^-v- -269.0
1 -^-v- -507.7
Top of page.
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 = -153.2366438867 Hartrees
Top of page.
-> Return to Molecular Structure Page.
-> Return to Chemistry Home Page