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

using model chemistry: MP4/6-31G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes CS 1A'
Energy calculated at MP4/6-31G*
 hartrees
Energy at 0K-168.250330
Energy at 298.15K-168.251313
HF Energy-167.754791
Nuclear repulsion energy58.205346
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 MP4/6-31G*
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' 3676 3509        
2 A' 2292 2188        
3 A' 1255 1198        
4 A' 813 776        
5 A' 548 523        
6 A" 589 563        

Unscaled Zero Point Vibrational Energy (zpe) 4585.6 cm-1
Scaled (by 0.9548) Zero Point Vibrational Energy (zpe) 4378.4 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 MP4/6-31G*
ABC
27.54531 0.35677 0.35221

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP4/6-31G*

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
H1 1.850 0.630 0.000
N2 1.181 -0.130 0.000
C3 -0.042 0.035 -0.000
O4 -1.233 0.009 0.000

Atom - Atom Distances (Å)
  H1 N2 C3 O4
H11.01231.98293.1447
N21.01231.23332.4174
C31.98291.23331.1915
O43.14472.41741.1915

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 123.718 N2 C3 O4 171.055
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability