CNO-, isocyanate ion

C3 = N1 - O2
The ion charge is -1.

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= 0.636
O2 charge=-0.704
C3 charge=-0.931
with a dipole moment of 1.88903 Debye

Bond Lengths:

between N1 and O2: distance=1.276 ang___ between N1 and C3: distance=1.204 ang___
between O2 and C3: distance=2.479 ang___

Bond Angles:

for C3-N1-O2: angle=179.8 deg___

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Bond Orders (Mulliken):

between N1 and O2: order=0.667___ between N1 and C3: order=2.326___
between O2 and C3: order=0.182___

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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. 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 N1-O2 with 1.9976 electrons
__has 52.71% N 1 character in a sp1.45 hybrid
__has 47.29% O 2 character in a s0.79 p3 hybrid

2. A bonding orbital for N1-C3 with 1.9974 electrons
__has 66.90% N 1 character in a sp0.68 hybrid
__has 33.10% C 3 character in a sp2.22 hybrid

3. A bonding orbital for N1-C3 with 1.9929 electrons
__has 65.96% N 1 character in a p-pi orbital ( 99.84% p 0.16% d)
__has 34.04% C 3 character in a p-pi orbital ( 99.48% p 0.52% d)

4. A bonding orbital for N1-C3 with 1.9929 electrons
__has 65.96% N 1 character in a p-pi orbital ( 99.84% p 0.16% d)
__has 34.04% C 3 character in a p-pi orbital ( 99.48% p 0.52% d)

8. A lone pair orbital for O2 with 1.9799 electrons
__made from a sp0.25 hybrid

9. A lone pair orbital for O2 with 1.8738 electrons
__made from a p-pi orbital ( 99.94% p 0.06% d)

10. A lone pair orbital for O2 with 1.8738 electrons
__made from a p-pi orbital ( 99.94% p 0.06% d)

11. A lone pair orbital for C3 with 1.9730 electrons
__made from a sp0.43 hybrid

71. A antibonding orbital for N1-C3 with 0.1202 electrons
__has 34.04% N 1 character in a p-pi orbital ( 99.84% p 0.16% d)
__has 65.96% C 3 character in a p-pi orbital ( 99.48% p 0.52% d)

72. A antibonding orbital for N1-C3 with 0.1202 electrons
__has 34.04% N 1 character in a p-pi orbital ( 99.84% p 0.16% d)
__has 65.96% C 3 character in a p-pi orbital ( 99.48% p 0.52% d)

-With core pairs on: N 1 O 2 C 3 -

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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, 8, for O2 with the antibonding acceptor orbital, 70, for N1-C3 is 86.9 kJ/mol.

The interaction of the second lone pair donor orbital, 9, for O2 with the third antibonding acceptor orbital, 72, for N1-C3 is 225. kJ/mol.

The interaction of the third lone pair donor orbital, 10, for O2 with the second antibonding acceptor orbital, 71, for N1-C3 is 225. kJ/mol.

The interaction of lone pair donor orbital, 11, for C3 with the antibonding acceptor orbital, 69, for N1-O2 is 85.6 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.

15 ----- 9.368

14 ----- 8.025

13 ----- 6.111 12 ----- 6.111

11 -^-v- 0.451 10 -^-v- 0.450


9 -^-v- -0.919


8 -^-v- -4.411 7 -^-v- -4.412


6 -^-v- -6.450


5 -^-v- -14.85


4 -^-v- -20.87


3 -^-v- -260.1


2 -^-v- -373.3


1 -^-v- -500.5

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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 = -168.0920318847 Hartrees

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