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

using model chemistry: QCISD/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 QCISD/6-31G**
 hartrees
Energy at 0K-168.236169
Energy at 298.15K-168.237187
HF Energy-167.762730
Nuclear repulsion energy58.756531
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 QCISD/6-31G**
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
(Å4/u)
Dep P Dep U
1 A' 3781 3560 131.53      
2 A' 2338 2201 612.70      
3 A' 1329 1251 0.48      
4 A' 824 776 252.08      
5 A' 559 526 82.19      
6 A" 613 577 3.90      

Unscaled Zero Point Vibrational Energy (zpe) 4721.6 cm-1
Scaled (by 0.9414) Zero Point Vibrational Energy (zpe) 4444.9 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 QCISD/6-31G**
ABC
27.75486 0.36350 0.35880

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

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
H1 1.476 -1.244 0.000
N2 0.486 -1.074 0.000
C3 0.000 0.050 0.000
O4 -0.609 1.058 0.000

Atom - Atom Distances (Å)
  H1 N2 C3 O4
H11.00471.96263.1061
N21.00471.22372.3963
C31.96261.22371.1782
O43.10612.39631.1782

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 123.159 N2 C3 O4 172.235
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability