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 C2H4O (Ethylene oxide)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
0.85500 0.73787 0.47026
Rotational Constants from 1966Herzberg
Calculated rotational constants for C2H4O (Ethylene oxide).

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
rCC 1.459 2 3 1995Kuchitsu(II/23)
rCO 1.425 1 2 1995Kuchitsu(II/23)
rCH 1.084 2 4 1995Kuchitsu(II/23)
aCOC 61.594 2 1 3 1995Kuchitsu(II/23) from symmetry
aHCH 116.75 4 2 5 1995Kuchitsu(II/23)
aHCC 119.078 3 2 4 1995Kuchitsu(II/23) from symmetry
aHCO 114.704 1 3 6 1995Kuchitsu(II/23) from symmetry
dHCCO 103.017 1 3 2 4 1995Kuchitsu(II/23) from symmetry
aCCO 59.2 1 3 2 1995Kuchitsu(II/23) from symmetry
picture of Ethylene oxide

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
C-C 1
C-O 2
H-C 4

Atom x (Å) y (Å) z (Å)
O1 0.0000 0.0000 0.8517
C2 0.0000 0.7297 -0.3725
C3 0.0000 -0.7297 -0.3725
H4 -0.9230 1.2565 -0.5859
H5 0.9230 1.2565 -0.5859
H6 0.9230 -1.2565 -0.5859
H7 -0.9230 -1.2565 -0.5859

Atom - Atom Distances (Å)

  O1 C2 C3 H4 H5 H6 H7

Calculated geometries for C2H4O (Ethylene oxide).
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squib reference DOI
1966Herzberg Herzberg, G., Electronic spectra and electronic structure of polyatomic molecules,Van Nostrand,New York, 1966  
1995Kuchitsu(II/23) Kuchitsu (ed.), Landolt-Bornstein: Group II: Molecules and Radicals Volume 23: Structure Data for Free Polyatomic Molecules. Springer. Berlin. 1995  

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