National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 22May 2022
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 H2O (Water)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
27.87700 14.51200 9.28500
Rotational Constants from 1966Herzberg
Calculated rotational constants for H2O (Water).

Point Group C2v

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
rOH 0.958 1 2 1979Hoy/Bun:1 re
aHOH 104.4776 2 1 3 1979Hoy/Bun:1 equilibrium
picture of Water

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
H-O 2

Atom x (Å) y (Å) z (Å)
O1 0.0000 0.0000 0.1173
H2 0.0000 0.7572 -0.4692
H3 0.0000 -0.7572 -0.4692

Atom - Atom Distances (Å)

  O1 H2 H3

Calculated geometries for H2O (Water).
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squib reference DOI
1966Herzberg Herzberg, G., Electronic spectra and electronic structure of polyatomic molecules,Van Nostrand,New York, 1966  
1979Hoy/Bun:1 AR Hoy, PR Bunker, "A precise Solution of the Rotation Beninding Schrodinger Equation for a Triatomic Molecule with Application to the Water Molecule" J. Molecular Spectroscopy 74, 1-8, 1979 10.1016/0022-2852(79)90019-5

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