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All results from a given calculation for HNCO (Isocyanic acid)

using model chemistry: CISD/3-21G

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes CS 1A'
Energy calculated at CISD/3-21G
 hartrees
Energy at 0K-167.106514
Energy at 298.15K-167.107396
Nuclear repulsion energy58.838135
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 A' 3823 3599 272.75      
2 A' 2391 2251 521.91      
3 A' 1344 1265 11.64      
4 A' 609 573 68.88      
5 A' 510 480 340.07      
6 A" 590 555 1.72      

Unscaled Zero Point Vibrational Energy (zpe) 4633.4 cm-1
Scaled (by 0.9413) Zero Point Vibrational Energy (zpe) 4361.5 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
ABC
53.75755 0.36045 0.35805

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

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
H1 1.467 -1.420 0.000
N2 0.555 -1.015 0.000
C3 0.000 0.045 0.000
O4 -0.669 1.032 0.000

Atom - Atom Distances (Å)
  H1 N2 C3 O4
H10.99782.07343.2521
N20.99781.19702.3855
C32.07341.19701.1924
O43.25212.38551.1924

picture of Isocyanic acid state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
H1 N2 C3 141.560 N2 C3 O4 173.496
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability