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

using model chemistry: QCISD/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 QCISD/3-21G*
 hartrees
Energy at 0K-167.137647
Energy at 298.15K-167.138529
HF Energy-166.806733
Nuclear repulsion energy58.359348
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/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 3579 204.20      
2 A' 2308 2218 407.38      
3 A' 1282 1233 9.11      
4 A' 618 594 231.57      
5 A' 539 518 153.92      
6 A" 562 540 0.18      

Unscaled Zero Point Vibrational Energy (zpe) 4516.4 cm-1
Scaled (by 0.9611) Zero Point Vibrational Energy (zpe) 4340.7 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/3-21G*
ABC
45.22260 0.35542 0.35265

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

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
H1 1.631 -1.223 0.000
N2 0.660 -0.964 0.000
C3 0.000 0.047 0.000
O4 -0.782 0.961 0.000

Atom - Atom Distances (Å)
  H1 N2 C3 O4
H11.00462.06743.2544
N21.00461.20832.4057
C32.06741.20831.2024
O43.25442.40571.2024

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 138.016 N2 C3 O4 172.577
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability