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 CH2CO (Ketene)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
9.37000 0.34335 0.33076
Rotational Constants from 1966Herzberg
Calculated rotational constants for CH2CO (Ketene).

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
rCO 1.162 2 3 1998Kuc rs structure
rCC 1.314 1 2 1998Kuc
rCH 1.083 1 4 1998Kuc rs structure
aHCH 122.56 4 1 5 1998Kuc
aHCC 118.72 2 1 4 1998Kuc by symmetry
picture of Ketene

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=C 1
H-C 2

Atom x (Å) y (Å) z (Å)
C1 0.0000 0.0000 0.0000
C2 0.0000 0.0000 1.3150
O3 0.0000 0.0000 2.4750
H4 0.0000 0.9451 -0.5206
H5 0.0000 -0.9451 -0.5206

Atom - Atom Distances (Å)

  C1 C2 O3 H4 H5

Calculated geometries for CH2CO (Ketene).
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squib reference DOI
1966Herzberg Herzberg, G., Electronic spectra and electronic structure of polyatomic molecules,Van Nostrand,New York, 1966  
1998Kuc K Kuchitsu(ed) "Structure of Free Polyatomic Molecules - Basic Data" Springer, Berlin, 1998  

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