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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II.A.3. (XII.A.1.)

Listing of experimental geometry data for HCOOH (Formic acid)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
2.58548 0.40211 0.34745
Rotational Constants from 1966Herzberg
Calculated rotational constants for HCOOH (Formic 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
rCO 1.202 1 3 1966Herzberg
rCO 1.343 1 2 1966Herzberg
rCH 1.097 1 4 1966Herzberg
rOH 0.972 2 5 1966Herzberg
aOCO 124.9 2 1 3 1966Herzberg
aHCO 124.1 3 1 4 1966Herzberg
aHOC 106.3 1 2 5 1966Herzberg
picture of Formic acid

Bond descriptions

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

Atom x (Å) y (Å) z (Å)
C1 0.0000 0.4199 0.0000
O2 -1.0543 -0.4121 0.0000
O3 1.1506 0.0721 0.0000
H4 -0.0799 1.5140 0.0000
H5 -0.6905 -1.3134 0.0000

Atom - Atom Distances (Å)

  C1 O2 O3 H4 H5

Calculated geometries for HCOOH (Formic acid).
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squib reference DOI
1966Herzberg Herzberg, G., Electronic spectra and electronic structure of polyatomic molecules,Van Nostrand,New York, 1966  

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