National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
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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II.A.3. (XII.A.1.)

Listing of experimental geometry data for HNO2 (Nitrous acid)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
3.09855 0.41778 0.36749
Rotational Constants from 1985Dee/Mil:962
Calculated rotational constants for HNO2 (Nitrous acid).

Point Group Cs

Internal coordinates

(distances (r) in Å) (angles (a) in degrees) (dihedrals (d) in degrees)
Description Value Connectivity Reference Comment
Atom 1 Atom 2 Atom 3 Atom 4
rNO 1.442 2 3 1972Fin/Cox:548
rNO 1.169 3 4 1972Fin/Cox:548
aONO 110.6 2 3 4 1972Fin/Cox:548
rOH 0.959 1 2 1972Fin/Cox:548
aHON 102.1 1 2 3 1972Fin/Cox:548
picture of Nitrous acid

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
H-O 1
N-O 1
N=O 1

Atom x (Å) y (Å) z (Å)
H1 1.7545 -0.1823 0.0000
O2 0.8942 -0.6061 0.0000
N3 0.0000 0.5252 0.0000
O4 -1.1135 0.1693 0.0000

Atom - Atom Distances (Å)

  H1 O2 N3 O4

Calculated geometries for HNO2 (Nitrous acid).
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squib reference DOI
1972Fin/Cox:548 J. Chem. Soc. Faraday Trans II, 68, 548 (1972) 10.1039/f29726800548
1985Dee/Mil:962 Deeley, C.M.; Mills, I.M.; Halonen, L.O.; Kauppinen, J. "Vibration-rotation spectra of ntrous acid, HONO." Can. J. Phys. 63, 962-965 (1985) 10.1139/p85-157

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