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 1.6274 electrons
__has 54.19% C 1 character in a s0.75 p3 hybrid
__has 45.81% C 2 character in a s0.51 p3 hybrid
2. A bonding orbital for C1-C8 with 1.9911 electrons
__has 54.65% C 1 character in a sp2.08 hybrid
__has 45.35% C 8 character in a sp2.65 hybrid
3. A bonding orbital for C1-H12 with 1.9174 electrons
__has 63.64% C 1 character in a s0.60 p3 hybrid
__has 36.36% H12 character in a s orbital
4. A bonding orbital for C1-H13 with 1.8626 electrons
__has 63.24% C 1 character in a sp2.22 hybrid
__has 36.76% H13 character in a s orbital
5. A bonding orbital for C2-C3 with 1.9939 electrons
__has 49.79% C 2 character in a sp2.23 hybrid
__has 50.21% C 3 character in a sp2.10 hybrid
6. A bonding orbital for C2-H6 with 1.9744 electrons
__has 63.04% C 2 character in a sp2.77 hybrid
__has 36.96% H 6 character in a s orbital
7. A bonding orbital for C2-H7 with 1.9864 electrons
__has 62.83% C 2 character in a sp2.57 hybrid
__has 37.17% H 7 character in a s orbital
8. A bonding orbital for C3-H4 with 1.9907 electrons
__has 62.70% C 3 character in a sp2.23 hybrid
__has 37.30% H 4 character in a s orbital
9. A bonding orbital for C3-H5 with 1.9866 electrons
__has 62.81% C 3 character in a sp2.21 hybrid
__has 37.19% H 5 character in a s orbital
10. A bonding orbital for C8-H9 with 1.9821 electrons
__has 61.64% C 8 character in a s0.94 p3 hybrid
__has 38.36% H 9 character in a s orbital
11. A bonding orbital for C8-H10 with 1.9914 electrons
__has 60.88% C 8 character in a s0.97 p3 hybrid
__has 39.12% H10 character in a s orbital
12. A bonding orbital for C8-H11 with 1.9900 electrons
__has 60.53% C 8 character in a s0.96 p3 hybrid
__has 39.47% H11 character in a s orbital
17. A lone pair orbital for C3 with 0.5627 electrons
__made from a s0.18 p3 hybrid
-With core pairs on: C 1 C 2 C 3 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, 1, for C1-C2 with
the lone pair acceptor orbital, 17, for C3 is 1028 kJ/mol.
The interaction of bonding donor orbital, 3, for C1-H12 with
the lone pair acceptor orbital, 17, for C3 is 31.0 kJ/mol.
The interaction of bonding donor orbital, 4, for C1-H13 with
the lone pair acceptor orbital, 17, for C3 is 363. kJ/mol.
The interaction of bonding donor orbital, 5, for C2-C3 with
the lone pair acceptor orbital, 17, for C3 is 69.2 kJ/mol.
The interaction of bonding donor orbital, 10, for C8-H9 with
the antibonding acceptor orbital, 139, for C1-C2 is 22.4 kJ/mol.
The interaction of lone pair donor orbital, 17, for C3 with
the antibonding acceptor orbital, 142, for C1-H13 is 20.0 kJ/mol.
The interaction of lone pair donor orbital, 17, for C3 with
the antibonding acceptor orbital, 143, for C2-C3 is 25.9 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.
20 ----- -3.773
19 ----- -3.894
18 ----- -5.450
17 ----- -7.899
16 -^-v- -13.82
15 -^-v- -14.02
14 -^-v- -15.04
13 -^-v- -15.32
12 -^-v- -15.68
11 -^-v- -16.64
10 -^-v- -17.37
9 -^-v- -18.35
8 -^-v- -20.80
7 -^-v- -21.20
6 -^-v- -23.62
5 -^-v- -27.48
4 -^-v- -271.3
3 -^-v- -273.4
2 -^-v- -273.8
1 -^-v- -274.0
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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 = -157.5537861409 Hartrees
* Linear butyl cation rearranges easily
to this cyclic cation or the
2-dehydro-butane cation, which is
lower in energy. The linear cation cannot
be obtained by minimization procedures using LSDA/DFT or ab initio
theory. However, the B3LYP energies from Gaussian98 are: linear -156.6265915 H
and cyclic -156.6581973 H.
Because two of the C-C
bond orders in the ring are so small, and the corresponding
bond lengths are so long,
it is difficult to decide
whether this is a very distorted conformer
of 1-dehydro-butane cation or a complex of ethyl cation with ethylene.
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