HSCN, Isothiocyanic acid

H3
|
S1 - C2 E N4
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

S1 charge=-0.055
C2 charge= 0.240
H3 charge= 0.191
N4 charge=-0.376
with a dipole moment of 3.69022 Debye

Bond Lengths:

between S1 and C2: distance=1.706 ang___ between S1 and H3: distance=1.366 ang___
between C2 and N4: distance=1.175 ang___

Bond Angles:

for H3-S1-C2: angle=94.86 deg___ for N4-C2-S1: angle=175.8 deg___

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Bond Orders (Mulliken):

between S1 and C2: order=1.107___ between S1 and H3: order=0.940___
between C2 and N4: order=2.602___

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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 S1-C2 with 1.9942 electrons
__has 42.79% S 1 character in a s0.59 p3 hybrid
__has 57.21% C 2 character in a sp1.01 hybrid

2. A bonding orbital for S1-H3 with 1.9758 electrons
__has 57.23% S 1 character in a s0.48 p3 hybrid
__has 42.77% H 3 character in a s orbital

3. A bonding orbital for C2-N4 with 1.9989 electrons
__has 43.07% C 2 character in a sp1.00 hybrid
__has 56.93% N 4 character in a sp1.18 hybrid

4. A bonding orbital for C2-N4 with 1.9972 electrons
__has 43.27% C 2 character in a p-pi orbital ( 99.80% p 0.20% d)
__has 56.73% N 4 character in a p-pi orbital ( 99.62% p 0.38% d)

5. A bonding orbital for C2-N4 with 1.9905 electrons
__has 48.68% C 2 character in a p3 hybrid
__has 51.32% N 4 character in a p3 hybrid

13. A lone pair orbital for S1 with 1.9768 electrons
__made from a sp0.42 hybrid

14. A lone pair orbital for S1 with 1.9039 electrons
__made from a p-pi orbital ( 99.90% p 0.10% d)

15. A lone pair orbital for N4 with 1.9690 electrons
__made from a sp0.85 hybrid

-With core pairs on: S 1 S 1 S 1 S 1 S 1 C 2 N 4 -

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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 S1-H3 with the third antibonding acceptor orbital, 85, for C2-N4 is 39.8 kJ/mol.

The interaction of lone pair donor orbital, 13, for S1 with the antibonding acceptor orbital, 83, for C2-N4 is 65.1 kJ/mol.

The interaction of the second lone pair donor orbital, 14, for S1 with the second antibonding acceptor orbital, 84, for C2-N4 is 159. kJ/mol.

The interaction of lone pair donor orbital, 15, for N4 with the antibonding acceptor orbital, 81, for S1-C2 is 62.2 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.

19 ----- -0.408

18 ----- -0.654

17 ----- -0.867


16 ----- -2.098


15 -^-v- -7.180


14 -^-v- -8.709

13 -^-v- -8.965

12 -^-v- -9.752


11 -^-v- -11.11


10 -^-v- -13.79


9 -^-v- -20.60


8 -^-v- -22.89


7 -^-v- -156.6

6 -^-v- -156.9

5 -^-v- -157.1


4 -^-v- -209.8


3 -^-v- -268.4


2 -^-v- -377.8


1 -^-v- -2389.

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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 = -491.6904451068 Hartrees

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