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All results from a given calculation for HNCS (Isothiocyanic acid)

using model chemistry: CISD/3-21G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 2 yes C*V 1Σ

Conformer 1 (CS)

Jump to S1C2
Energy calculated at CISD/3-21G*
 hartrees
Energy at 0K-488.335591
Energy at 298.15K 
HF Energy-488.034580
Nuclear repulsion energy79.467182
The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.
Vibrational Frequencies calculated at CISD/3-21G*
Rotational Constants (cm-1) from geometry optimized at CISD/3-21G*
See section I.F.4 to change rotational constant units
Geometric Data calculated at CISD/3-21G*
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability

Conformer 2 (C*V)

Jump to S1C1
Energy calculated at CISD/3-21G*
 hartrees
Energy at 0K-488.335601
Energy at 298.15K-488.335857
HF Energy-488.034467
Nuclear repulsion energy79.482754
The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.
Vibrational Frequencies calculated at CISD/3-21G*
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 Σ 3883 3628 754.72      
2 Σ 2244 2097 575.17      
3 Σ 839 784 53.07      
4 Π 509 475 1.17      
4 Π 509 475 1.17      
5 Π 202 189 241.75      
5 Π 202 189 241.75      

Unscaled Zero Point Vibrational Energy (zpe) 4193.6 cm-1
Scaled (by 0.9344) Zero Point Vibrational Energy (zpe) 3918.5 cm-1
See section III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.
Rotational Constants (cm-1) from geometry optimized at CISD/3-21G*
B
0.19166

See section I.F.4 to change rotational constant units
Geometric Data calculated at CISD/3-21G*

Point Group is C∞v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
N1 0.000 0.000 -1.682
C2 0.000 0.000 -0.507
S3 0.000 0.000 1.093
H4 0.000 0.000 -2.674

Atom - Atom Distances (Å)
  N1 C2 S3 H4
N11.17522.77460.9921
C21.17521.59932.1674
S32.77461.59933.7667
H40.99212.16743.7667

picture of Isothiocyanic acid state 1 conformation 2
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
N1 C2 S3 180.000 C2 N1 H4 180.000
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability