NH3...NH3, Ammonia dimer

N1H2 - N7 - H8
/ | \
Tell me about the atomic charges, dipole moment, bond lengths, angles, bond orders,
molecular orbital energies, or total energy.
Tell me about the best Lewis structure.

Atomic Charges and Dipole Moment

N1 charge=-0.758
H2 charge= 0.320
H3 charge= 0.292
H4 charge= 0.286
H5 charge= 0.249
H6 charge= 0.346
N7 charge=-1.083
H8 charge= 0.347
with a dipole moment of 3.06505 Debye

Bond Lengths:

between N1 and H2: distance=2.210 ang___ between N1 and H3: distance=1.024 ang___
between N1 and H4: distance=1.024 ang___ between N1 and H5: distance=1.024 ang___
between H2 and N7: distance=1.034 ang___ between H6 and N7: distance=1.024 ang___
between N7 and H8: distance=1.024 ang___

Bond Angles:

for H3-N1-H2: angle=104.9 deg___ for H4-N1-H2: angle=107.4 deg___
for H5-N1-H2: angle=120.5 deg___ for H6-H2-N1: angle=148.0 deg___
for N7-H2-N1: angle=171.7 deg___ for H8-H2-N1: angle=147.7 deg___

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Bond Orders (Mulliken):

between N1 and H2: order=-0.098___ between N1 and H3: order=0.914___
between N1 and H4: order=0.915___ between N1 and H5: order=0.915___
between H2 and N7: order=0.900___ between H6 and N7: order=0.937___
between N7 and H8: order=0.937___

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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 N1-H3 with 1.9997 electrons
__has 67.90% N 1 character in a sp2.86 hybrid
__has 32.10% H 3 character in a s orbital

2. A bonding orbital for N1-H4 with 1.9997 electrons
__has 67.86% N 1 character in a sp2.86 hybrid
__has 32.14% H 4 character in a s orbital

3. A bonding orbital for N1-H5 with 1.9996 electrons
__has 67.78% N 1 character in a sp2.86 hybrid
__has 32.22% H 5 character in a s orbital

4. A bonding orbital for H2-N7 with 1.9995 electrons
__has 30.09% H 2 character in a s orbital
__has 69.91% N 7 character in a sp2.58 hybrid

5. A bonding orbital for H6-N7 with 1.9996 electrons
__has 33.02% H 6 character in a s orbital
__has 66.98% N 7 character in a sp2.95 hybrid

6. A bonding orbital for N7-H8 with 1.9996 electrons
__has 66.98% N 7 character in a sp2.95 hybrid
__has 33.02% H 8 character in a s orbital

9. A lone pair orbital for N1 with 1.9908 electrons
__made from a s0.86 p3 hybrid

10. A lone pair orbital for N7 with 1.9983 electrons
__made from a s0.82 p3 hybrid

-With core pairs on: N 1 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 lone pair donor orbital, 9, for N1 with the antibonding acceptor orbital, 82, for H2-N7 is 22.0 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.

14 ----- 3.401 13 ----- 3.373

12 ----- 2.231

11 ----- 0.810

10 -^-v- -5.230

9 -^-v- -6.569

8 -^-v- -10.39

7 -^-v- -10.49

6 -^-v- -11.64
5 -^-v- -11.67

4 -^-v- -19.98

3 -^-v- -21.28

2 -^-v- -375.7

1 -^-v- -377.0

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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 = -113.1697395450 Hartrees

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