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

using model chemistry: CCSD/6-31G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes CS 1A'
Energy calculated at CCSD/6-31G*
 hartrees
Energy at 0K-168.223444
Energy at 298.15K-168.224456
HF Energy-167.758507
Nuclear repulsion energy58.824831
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 CCSD/6-31G*
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' 3714 3507        
2 A' 2360 2229        
3 A' 1347 1272        
4 A' 804 759        
5 A' 561 530        
6 A" 619 584        

Unscaled Zero Point Vibrational Energy (zpe) 4702.1 cm-1
Scaled (by 0.9443) Zero Point Vibrational Energy (zpe) 4440.2 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 CCSD/6-31G*
ABC
28.31252 0.36433 0.35971

See section I.F.4 to change rotational constant units
Geometric Data calculated at CCSD/6-31G*

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
H1 1.453 -1.287 0.000
N2 0.465 -1.080 0.000
C3 0.000 0.050 0.000
O4 -0.588 1.068 0.000

Atom - Atom Distances (Å)
  H1 N2 C3 O4
H11.00951.97413.1163
N21.00951.22132.3919
C31.97411.22131.1759
O43.11632.39191.1759

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 124.222 N2 C3 O4 172.351
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability