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: mPW1PW91/STO-3G

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C2V 2A1
Energy calculated at mPW1PW91/STO-3G
Energy at 0K-202.255411
Energy at 298.15K 
HF Energy-202.255411
Nuclear repulsion energy60.486108
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 mPW1PW91/STO-3G
Mode Number Symmetry Frequency (cm-1) Scaled Frequency (cm-1) IR Intensities (km mol-1)
1 A1 1315 1156 0.60
2 A1 637 560 2.10
3 B2 1558 1370 7.08

Unscaled Zero Point Vibrational Energy (zpe) 1755.2 cm-1
Scaled (by 0.8789) Zero Point Vibrational Energy (zpe) 1542.6 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 mPW1PW91/STO-3G
5.59617 0.38887 0.36360

See section I.F.4 to change rotational constant units
Geometric Data calculated at mPW1PW91/STO-3G

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
N1 0.000 0.000 0.387
O2 0.000 1.164 -0.169
O3 0.000 -1.164 -0.169

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 128.929
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability

Charges from optimized geometry at mPW1PW91/STO-3G Charges (e)

Number Element Mulliken CHELPG AIM ESP
1 N 0.088      
2 O -0.044      
3 O -0.044      

Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)

  x y z Total
  0.000 0.000 -0.104 0.104

Electric Quadrupole moment
Quadrupole components in D Å

x -13.089 0.000 0.000
y 0.000 -15.476 0.000
z 0.000 0.000 -13.950
x 1.624 0.000 0.000
y 0.000 -1.956 0.000
z 0.000 0.000 0.332

Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.

  x y z
x 0.380 0.000 0.000
y 0.000 2.556 0.000
z 0.000 0.000 0.577

<r2> (averge value of r2) Å2

<r2> 32.040
(<r2>)1/2 5.660