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 C4H4O (Furan)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
0.31512 0.30843 0.15580
Rotational Constants from 1966Herzberg
Calculated rotational constants for C4H4O (Furan).

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 1.362 1 2 1966Herzberg
rCC 1.361 2 4 1966Herzberg
rCC 1.431 4 5 1966Herzberg
rCH 1.076 2 6 1966Herzberg
aCOC 106.6 2 1 3 1966Herzberg
aCCO 110.7 1 2 4 1966Herzberg
aCCC 106.1 2 4 5 1966Herzberg
aHCC 127.9 2 4 8 1966Herzberg
aHCO 115.9 1 2 6 1966Herzberg
aHCC 133.4 4 2 6 1966Herzberg by symmetry
aHCC 126 5 4 8 1966Herzberg by symmetry
picture of Furan

Bond descriptions

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

Atom x (Å) y (Å) z (Å)
O1 0.0000 0.0000 1.1626
C2 0.0000 1.0920 0.3487
C3 0.0000 -1.0920 0.3487
C4 0.0000 0.7169 -0.9596
C5 0.0000 -0.7169 -0.9596
H6 0.0000 2.0473 0.8439
H7 0.0000 -2.0473 0.8439
H8 0.0000 1.3509 -1.8290
H9 0.0000 -1.3509 -1.8290

Atom - Atom Distances (Å)

  O1 C2 C3 C4 C5 H6 H7 H8 H9

Calculated geometries for C4H4O (Furan).
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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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