National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 19April 2018
NIST Standard Reference Database 101
IIntroduction
IIExperimental data
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IVData comparisons
VCost comparisons
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XOlder CCCBDB versions
XIIGeometries
XIII Vibrations
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XVEntropy data
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XVIIIon data
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XIXIndex of properties
XXH-bond dimers
XXIOddities

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III.D.1.a.

All results from a given calculation for HCNO (fulminic acid)

using model chemistry: CISD/6-31G*

States and conformations

State Conformation minimum conformation conformer description state description
1 1 no C*V 1Σ
1 2 yes CS 1A'

Conformer 1 (C*V)

Jump to S1C2
Energy calculated at CISD/6-31G*
 hartrees
Energy at 0K-168.059917
Energy at 298.15K 
HF Energy-167.628687
Nuclear repulsion energy60.396009
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 CISD/6-31G*
Mode Number Symmetry Frequency (cm-1) Scaled Frequency (cm-1) IR Intensities (km mol-1)
1 Σ 3620 3351 260.57
2 Σ 2427 2247 332.78
3 Σ 1321 1223 165.25
4 Π 588 545 0.19
4 Π 588 545 0.19
5 Π 357 331 86.43
5 Π 357 331 86.43

Unscaled Zero Point Vibrational Energy (zpe) 4628.9 cm-1
Scaled (by 0.9258) Zero Point Vibrational Energy (zpe) 4285.5 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 CISD/6-31G*
B
0.38231

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

Point Group is C∞v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
O1 0.000 0.000 1.186
N2 0.000 0.000 -0.025
C3 0.000 0.000 -1.178
H4 0.000 0.000 -2.239

Atom - Atom Distances (Å)

  O1 N2 C3 H4
O11.21042.36403.4247
N21.21041.15362.2143
C32.36401.15361.0606
H43.42472.21431.0606

picture of fulminic acid
More geometry information

Calculated Bond Angles

atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O1 N2 C3 180.000 N2 C3 H4 180.000
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability

Conformer 2 (CS)

Jump to S1C1
Energy calculated at CISD/6-31G*
 hartrees
Energy at 0K-168.059917
Energy at 298.15K 
HF Energy-167.628701
Nuclear repulsion energy60.392738
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 CISD/6-31G*

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