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.
Please note that your structure can't be well described by a single
Lewis structure, because of extensive delocalization.
Hybridization in the Best Lewis Structure
1. A bonding orbital for C1-C2 with 1.9863 electrons
__has 50.00% C 1 character in a sp1.06 hybrid
__has 50.00% C 2 character in a sp1.06 hybrid
2. A bonding orbital for C1-N3 with 1.8876 electrons
__has 50.21% C 1 character in a sp2.60 hybrid
__has 49.79% N 3 character in a s0.53 p3 hybrid
3. A bonding orbital for C1-C4 with 1.7995 electrons
__has 68.95% C 1 character in a s0.92 p3 hybrid
__has 31.05% C 4 character in a s0.35 p3 hybrid
4. A bonding orbital for C2-N5 with 1.8874 electrons
__has 50.20% C 2 character in a sp2.61 hybrid
__has 49.80% N 5 character in a s0.53 p3 hybrid
5. A bonding orbital for C2-C6 with 1.7998 electrons
__has 68.96% C 2 character in a s0.93 p3 hybrid
__has 31.04% C 6 character in a s0.36 p3 hybrid
6. A bonding orbital for N3-C4 with 1.9765 electrons
__has 63.98% N 3 character in a sp2.03 hybrid
__has 36.02% C 4 character in a s0.98 p3 hybrid
7. A bonding orbital for N3-C4 with 1.6538 electrons
__has 70.80% N 3 character in a p-pi orbital ( 99.50% p 0.50% d)
__has 29.20% C 4 character in a p-pi orbital ( 98.88% p 1.11% d)
8. A bonding orbital for N5-C6 with 1.9765 electrons
__has 63.98% N 5 character in a sp2.02 hybrid
__has 36.02% C 6 character in a s0.98 p3 hybrid
9. A bonding orbital for N5-C6 with 1.6539 electrons
__has 70.78% N 5 character in a p-pi orbital ( 99.50% p 0.50% d)
__has 29.22% C 6 character in a p-pi orbital ( 98.88% p 1.11% d)
16. A lone pair orbital for C1 with 0.6298 electrons
__made from a p3 hybrid
17. A lone pair orbital for C2 with 0.6298 electrons
__made from a p3 hybrid
18. A lone pair orbital for N3 with 1.9601 electrons
__made from a sp0.90 hybrid
19. A lone pair orbital for C4 with 1.9502 electrons
__made from a sp0.51 hybrid
20. A lone pair orbital for N5 with 1.9601 electrons
__made from a sp0.90 hybrid
21. A lone pair orbital for C6 with 1.9500 electrons
__made from a sp0.51 hybrid
-With core pairs on: C 1 C 2 N 3 C 4 N 5 C 6 -
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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, 2, for C1-N3 with
the lone pair acceptor orbital, 17, for C2 is 43.6 kJ/mol.
The interaction of bonding donor orbital, 2, for C1-N3 with
the antibonding acceptor orbital, 138, for C1-C4 is 84.7 kJ/mol.
The interaction of bonding donor orbital, 3, for C1-C4 with
the lone pair acceptor orbital, 17, for C2 is 178. kJ/mol.
The interaction of bonding donor orbital, 3, for C1-C4 with
the antibonding acceptor orbital, 137, for C1-N3 is 30.7 kJ/mol.
The interaction of bonding donor orbital, 4, for C2-N5 with
the lone pair acceptor orbital, 16, for C1 is 43.8 kJ/mol.
The interaction of bonding donor orbital, 4, for C2-N5 with
the antibonding acceptor orbital, 140, for C2-C6 is 84.8 kJ/mol.
The interaction of bonding donor orbital, 5, for C2-C6 with
the lone pair acceptor orbital, 16, for C1 is 177. kJ/mol.
The interaction of bonding donor orbital, 5, for C2-C6 with
the antibonding acceptor orbital, 139, for C2-N5 is 30.7 kJ/mol.
The interaction of bonding donor orbital, 6, for N3-C4 with
the antibonding acceptor orbital, 136, for C1-C2 is 88.7 kJ/mol.
The interaction of the second bonding donor orbital, 7, for N3-C4 with
the lone pair acceptor orbital, 16, for C1 is 863. kJ/mol.
The interaction of bonding donor orbital, 8, for N5-C6 with
the antibonding acceptor orbital, 136, for C1-C2 is 88.7 kJ/mol.
The interaction of the second bonding donor orbital, 9, for N5-C6 with
the lone pair acceptor orbital, 17, for C2 is 863. kJ/mol.
The interaction of lone pair donor orbital, 16, for C1 with
the antibonding acceptor orbital, 139, for C2-N5 is 59.4 kJ/mol.
The interaction of lone pair donor orbital, 16, for C1 with
the antibonding acceptor orbital, 140, for C2-C6 is 52.9 kJ/mol.
The interaction of lone pair donor orbital, 17, for C2 with
the antibonding acceptor orbital, 137, for C1-N3 is 59.2 kJ/mol.
The interaction of lone pair donor orbital, 17, for C2 with
the antibonding acceptor orbital, 138, for C1-C4 is 53.1 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.
23 ----- -2.958
22 ----- -3.056
21 ----- -4.085
20 ----- -4.158
19 -^-v- -7.682 18 -^-v- -7.686
17 -^-v- -8.787
16 -^-v- -8.970
15 -^-v- -11.93 14 -^-v- -11.94
13 -^-v- -13.43
12 -^-v- -14.36
11 -^-v- -14.38
10 -^-v- -14.51
9 -^-v- -20.06
8 -^-v- -27.24
7 -^-v- -27.43
6 -^-v- -269.6 5 -^-v- -269.6
4 -^-v- -270.2
3 -^-v- -270.3
2 -^-v- -380.3 1 -^-v- -380.3
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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 = -261.7292419225 Hartrees
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