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.
Hybridization in the Best Lewis Structure
1. A bonding orbital for C1-H3 with 1.9618 electrons
__has 62.88% C 1 character in a sp2.34 hybrid
__has 37.12% H 3 character in a s orbital
2. A bonding orbital for C1-H4 with 1.9580 electrons
__has 62.77% C 1 character in a sp2.44 hybrid
__has 37.23% H 4 character in a s orbital
3. A bonding orbital for C1-C5 with 1.9996 electrons
__has 56.58% C 1 character in a p-pi orbital ( 99.74% p 0.26% d)
__has 43.42% C 5 character in a p-pi orbital ( 99.64% p 0.36% d)
4. A bonding orbital for C1-C5 with 1.9967 electrons
__has 57.06% C 1 character in a sp1.40 hybrid
__has 42.94% C 5 character in a sp1.77 hybrid
5. A bonding orbital for C2-H6 with 1.9918 electrons
__has 63.88% C 2 character in a sp0.90 hybrid
__has 36.12% H 6 character in a s orbital
6. A bonding orbital for C2-N7 with 1.9998 electrons
__has 43.86% C 2 character in a p-pi orbital ( 99.71% p 0.29% d)
__has 56.14% N 7 character in a p-pi orbital ( 99.62% p 0.38% d)
7. A bonding orbital for C2-N7 with 1.9998 electrons
__has 43.93% C 2 character in a p-pi orbital ( 99.71% p 0.29% d)
__has 56.07% N 7 character in a p-pi orbital ( 99.61% p 0.38% d)
8. A bonding orbital for C2-N7 with 1.9982 electrons
__has 42.77% C 2 character in a sp1.09 hybrid
__has 57.23% N 7 character in a sp1.15 hybrid
13. A lone pair orbital for C5 with 1.9596 electrons
__made from a sp0.54 hybrid
15. A lone pair orbital for N7 with 1.9783 electrons
__made from a sp0.85 hybrid
-With core pairs on: C 1 C 2 C 5 N 7 -
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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, 1, for C1-H3 with
the second lone pair acceptor orbital, 14, for C5 is 61.2 kJ/mol.
The interaction of bonding donor orbital, 2, for C1-H4 with
the second lone pair acceptor orbital, 14, for C5 is 71.0 kJ/mol.
The interaction of lone pair donor orbital, 13, for C5 with
the antibonding acceptor orbital, 111, for C2-H6 is 58.0 kJ/mol.
The interaction of lone pair donor orbital, 15, for N7 with
the antibonding acceptor orbital, 111, for C2-H6 is 40.1 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.
18 ----- -0.499
17 ----- -0.578
16 ----- -1.839
15 ----- -4.963
14 -^-v- -7.851
13 -^-v- -8.227
12 -^-v- -8.440 11 -^-v- -8.441
10 -^-v- -8.563
9 -^-v- -12.41
8 -^-v- -13.92
7 -^-v- -14.26
6 -^-v- -20.17
5 -^-v- -22.20
4 -^-v- -267.1
3 -^-v- -267.4
2 -^-v- -269.0
1 -^-v- -377.3
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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 = -170.7425889106 Hartrees
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