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

using model chemistry: MP2=FULL/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 MP2=FULL/3-21G*
 hartrees
Energy at 0K-167.145708
Energy at 298.15K-167.146636
Nuclear repulsion energy58.115620
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 MP2=FULL/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' 3724 3531 205.95      
2 A' 2345 2223 318.32      
3 A' 1268 1202 4.49      
4 A' 681 646 313.54      
5 A' 558 529 41.33      
6 A" 566 536 0.55      

Unscaled Zero Point Vibrational Energy (zpe) 4570.8 cm-1
Scaled (by 0.948) Zero Point Vibrational Energy (zpe) 4333.1 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 MP2=FULL/3-21G*
ABC
41.89409 0.35277 0.34982

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2=FULL/3-21G*

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
H1 1.713 -1.100 0.000
N2 0.723 -0.928 0.000
C3 0.000 0.052 0.000
O4 -0.846 0.910 0.000

Atom - Atom Distances (Å)
  H1 N2 C3 O4
H11.00542.06423.2547
N21.00541.21682.4165
C32.06421.21681.2059
O43.25472.41651.2059

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 136.316 N2 C3 O4 171.850
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability