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 C2H6 (Ethane)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
2.51967 0.68341 0.68341
Rotational Constants from 1998Kuc
Calculated rotational constants for C2H6 (Ethane).

Point Group D3d

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 1.536 1 2 1966Herzberg
rCH 1.091 1 3 1966Herzberg
aHCH 108 3 1 4 1966Herzberg
aHCC 110.91 1 2 6 1966Herzberg b ysymmetry
picture of Ethane

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
H-C 6

Atom x (Å) y (Å) z (Å)
C1 0.0000 0.0000 0.7680
C2 0.0000 0.0000 -0.7680
H3 -1.0192 0.0000 1.1573
H4 0.5096 0.8826 1.1573
H5 0.5096 -0.8826 1.1573
H6 1.0192 0.0000 -1.1573
H7 -0.5096 -0.8826 -1.1573
H8 -0.5096 0.8826 -1.1573

Atom - Atom Distances (Å)

  C1 C2 H3 H4 H5 H6 H7 H8

Calculated geometries for C2H6 (Ethane).
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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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