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

using model chemistry: HF/CEP-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 HF/CEP-31G*
 hartrees
Energy at 0K-31.441515
Energy at 298.15K-31.442612
Nuclear repulsion energy31.110942
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 HF/CEP-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' 3887 3490 167.17      
2 A' 2454 2204 1237.90      
3 A' 1436 1290 0.55      
4 A' 900 808 258.62      
5 A' 581 522 148.76      
6 A" 697 626 18.69      

Unscaled Zero Point Vibrational Energy (zpe) 4977.1 cm-1
Scaled (by 0.898) Zero Point Vibrational Energy (zpe) 4469.4 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 HF/CEP-31G*
ABC
26.29648 0.37156 0.36639

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

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
H1 1.018 -1.595 0.000
N2 0.113 -1.166 0.000
C3 0.000 0.048 0.000
O4 -0.226 1.184 0.000

Atom - Atom Distances (Å)
  H1 N2 C3 O4
H11.00211.93373.0452
N21.00211.21972.3743
C31.93371.21971.1578
O43.04522.37431.1578

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 120.679 N2 C3 O4 174.050
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/CEP-31G* Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 H 0.379      
2 N -0.228      
3 C -0.035      
4 O -0.116      


Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)
  x y z Total
  2.015 -1.102 0.000 2.297
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -14.255 -2.540 0.000
y -2.540 -19.167 0.000
z 0.000 0.000 -16.681
Traceless
 xyz
x 3.669 -2.540 0.000
y -2.540 -3.700 0.000
z 0.000 0.000 0.030
Polar
3z2-r20.061
x2-y24.913
xy-2.540
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 1.762 -0.485 0.000
y -0.485 4.272 0.000
z 0.000 0.000 1.537


<r2> (average value of r2) Å2
<r2> 30.479
(<r2>)1/2 5.521