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 N1-N2 with 0.9986 electrons
__has 50.00% N 1 character in a sp2.22 hybrid
__has 50.00% N 2 character in a sp2.22 hybrid
2. A bonding orbital for N1-H3 with 0.9970 electrons
__has 65.42% N 1 character in a s0.83 p3 hybrid
__has 34.58% H 3 character in a s orbital
3. A bonding orbital for N2-H4 with 0.9970 electrons
__has 65.42% N 2 character in a s0.83 p3 hybrid
__has 34.58% H 4 character in a s orbital
6. A lone pair orbital for N1 with 0.9979 electrons
__made from a sp1.11 hybrid
7. A lone pair orbital for N1 with 0.9799 electrons
__made from a p3 hybrid
8. A lone pair orbital for N2 with 0.9979 electrons
__made from a sp1.11 hybrid
9. A lone pair orbital for N2 with 0.9799 electrons
__made from a p3 hybrid
-With core pairs on: N 1 N 2 -
Up Electrons
1. A bonding orbital for N1-N2 with 0.9989 electrons
__has 50.00% N 1 character in a sp2.19 hybrid
__has 50.00% N 2 character in a sp2.19 hybrid
2. A bonding orbital for N1-H3 with 0.9494 electrons
__has 67.75% N 1 character in a s0.67 p3 hybrid
__has 32.25% H 3 character in a s orbital
3. A bonding orbital for N2-H4 with 0.9493 electrons
__has 67.74% N 2 character in a s0.67 p3 hybrid
__has 32.26% H 4 character in a s orbital
6. A lone pair orbital for N1 with 0.8491 electrons
__made from a sp0.97 hybrid
7. A lone pair orbital for N1 with 0.1872 electrons
__made from a p3 hybrid
8. A lone pair orbital for N2 with 0.8491 electrons
__made from a sp0.97 hybrid
9. A lone pair orbital for N2 with 0.1872 electrons
__made from a p3 hybrid
-With core pairs on: N 1 N 2 -
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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 N1-H3 with
the second lone pair acceptor orbital, 9, for N2 is 55.3 kJ/mol.
The interaction of bonding donor orbital, 3, for N2-H4 with
the second lone pair acceptor orbital, 7, for N1 is 55.3 kJ/mol.
The interaction of lone pair donor orbital, 6, for N1 with
the second lone pair acceptor orbital, 9, for N2 is 218. kJ/mol.
The interaction of lone pair donor orbital, 8, for N2 with
the second lone pair acceptor orbital, 7, for N1 is 218. 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.
13 ----- 6.422
12 ----- 4.623
11 ----- 1.626
10 ----- 1.431
9 -^--- -4.809
8 -^--- -5.294
7 -^-v- -9.826
6 -^-v- -10.70
5 -^-v- -13.73
4 -^-v- -17.76
3 -^-v- -25.38
2 -^-v- -378.8 1 -^-v- -378.8
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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 = -110.6309681580 Hartrees
* Note: The diimine singlet state is lower in energy.
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