## H2CSH+, thioformaldehyde onium ion

 H3 \ C1 = S2 / | H4 H5
The ion charge is 1.

## Atomic Charges and Dipole Moment

C1 charge=-0.192
S2 charge= 0.388
H3 charge= 0.295
H4 charge= 0.261
H5 charge= 0.247
with a dipole moment of 1.88678 Debye

## Bond Lengths:

between C1 and S2: distance=1.640 ang___ between C1 and H3: distance=1.101 ang___
between C1 and H4: distance=1.099 ang___ between S2 and H5: distance=1.379 ang___

## Bond Angles:

for H3-C1-S2: angle=116.8 deg___ for H4-C1-S2: angle=123.2 deg___
for H5-S2-C1: angle=99.02 deg___

## Bond Orders (Mulliken):

between C1 and S2: order=1.789___ between C1 and H3: order=0.897___
between C1 and H4: order=0.896___ between S2 and H5: order=0.925___

## 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 C1-S2 with 1.9998 electrons
__has 28.24% C 1 character in a p-pi orbital ( 99.51% p 0.49% d)
__has 71.76% S 2 character in a p-pi orbital ( 99.40% p 0.60% d)

2. A bonding orbital for C1-S2 with 1.9960 electrons
__has 54.33% C 1 character in a sp1.92 hybrid
__has 45.67% S 2 character in a s0.79 p3 hybrid

3. A bonding orbital for C1-H3 with 1.9918 electrons
__has 63.25% C 1 character in a sp2.10 hybrid
__has 36.75% H 3 character in a s orbital

4. A bonding orbital for C1-H4 with 1.9954 electrons
__has 63.29% C 1 character in a sp1.96 hybrid
__has 36.71% H 4 character in a s orbital

5. A bonding orbital for S2-H5 with 1.9860 electrons
__has 58.91% S 2 character in a s0.48 p3 hybrid
__has 41.09% H 5 character in a s orbital

12. A lone pair orbital for S2 with 1.9909 electrons

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

#### 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.

## 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.

16 ----- -3.187

15 ----- -5.637

14 ----- -7.293

13 ----- -11.12

12 -^-v- -15.77
11 -^-v- -15.87

10 -^-v- -17.91

9 -^-v- -19.34

8 -^-v- -22.83

7 -^-v- -28.20

6 -^-v- -163.8
5 -^-v- -163.9
4 -^-v- -164.0

3 -^-v- -216.8

2 -^-v- -275.8

1 -^-v- -2396.

## 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 = -437.8147427945 Hartrees