National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 19April 2018
NIST Standard Reference Database 101
IIExperimental data
IIICalculated data
IVData comparisons
VCost comparisons
VIInput and output files
VIITutorials and Units
VIIILinks to other sites
XOlder CCCBDB versions
XIII Vibrations
XIVReaction data
XVEntropy data
XVIBibliographic data
XVIIIon data
XVIIIBad calculations
XIXIndex of properties
XXH-bond dimers

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All results from a given calculation for NO2 (Nitrogen dioxide)

using model chemistry: MP4/3-21G

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C2V 2A1
Energy calculated at MP4/3-21G
Energy at 0K-203.270187
Energy at 298.15K 
HF Energy-202.820917
Nuclear repulsion energy59.390793
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 MP4/3-21G
Mode Number Symmetry Frequency (cm-1) Scaled Frequency (cm-1) IR Intensities (km mol-1)
1 A1 1888 1831  
2 A1 758i 735i  
3 B2 4165 4040  

Unscaled Zero Point Vibrational Energy (zpe) 2647.9 cm-1
Scaled (by 0.9698) Zero Point Vibrational Energy (zpe) 2567.9 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 MP4/3-21G
6.22269 0.36683 0.34641

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP4/3-21G

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
N1 0.000 0.000 0.367
O2 0.000 1.199 -0.161
O3 0.000 -1.199 -0.161

Atom - Atom Distances (Å)

  N1 O2 O3

picture of Nitrogen dioxide
More geometry information

Calculated Bond Angles

atom1 atom2 atom3 angle atom1 atom2 atom3 angle
O2 N1 O3 132.499
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability