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
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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 C4H6S (Thiophene, 2,5-dihydro-)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
0.22087 0.16006 0.09624
Rotational Constants from 1981Dur/Li:1564
Calculated rotational constants for C4H6S (Thiophene, 2,5-dihydro-).

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
rCH 1.095 2 6 1981Dur/Li:1564 in CH2
rCH 1.085 4 10 1981Dur/Li:1564
rCC 1.340 4 5 1981Dur/Li:1564
rCC 1.518 2 4 1981Dur/Li:1564
rCS 1.816 1 2 1981Dur/Li:1564
aHCH 109.8 6 2 7 1981Dur/Li:1564
aCCC 116.75 2 4 5 1981Dur/Li:1564 adjusted from listed value of 116.5 to get C=C bond length to agree with listed 1.34
aCCS 105 1 2 4 1981Dur/Li:1564 adjusted from listed value of 106.25 to get C=C bond distance to agree with listed value of 1.34
aCSC 96.5 2 1 3 1981Dur/Li:1564
aHCC 121.75 5 4 10 1981Dur/Li:1564
picture of Thiophene, 2,5-dihydro-

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
H-C 6
C=C 1
C-C 2
C-S 2

Atom x (Å) y (Å) z (Å)
S1 0.0000 0.0000 1.2290
C2 0.0000 1.3548 0.0197
C3 0.0000 -1.3548 0.0197
C4 0.0000 0.6716 -1.3358
C5 0.0000 -0.6716 -1.3358
H6 -0.8945 1.9701 0.1628
H7 0.8945 1.9701 0.1628
H8 0.8945 -1.9701 0.1628
H9 -0.8945 -1.9701 0.1628
H10 0.0000 1.2393 -2.2605
H11 0.0000 -1.2393 -2.2605

Atom - Atom Distances (Å)

  S1 C2 C3 C4 C5 H6 H7 H8 H9 H10 H11

Calculated geometries for C4H6S (Thiophene, 2,5-dihydro-).
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squib reference DOI
1981Dur/Li:1564 During, Li, During, Spectra and structure of small ring compounds. XLII. Microwave spectrum of 2,5-dihydrothiphene, J. Chem., Phys., Vol. 74, #3, pgs. 1564-1567 10.1063/1.441297

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