National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 18October 2016
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 C4H2O3 (Maleic Anhydride)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
0.22963 0.08272 0.06081
Rotational Constants from 2010Vog/Alt:153
Calculated rotational constants for C4H2O3 (Maleic Anhydride).

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 1.485 2 5 2010Vog/Alt:153
rCC 1.332 6 7 2010Vog/Alt:153
rCO 1.386 1 2 2010Vog/Alt:153
rCO 1.192 2 4 2010Vog/Alt:153
rHC 1.078 5 8 2010Vog/Alt:153 assumed
aCCC 107.8 2 6 7 2010Vog/Alt:153
aCCO 129.2 4 2 6 2010Vog/Alt:153
aHCC 129.7 6 7 9 2010Vog/Alt:153 assumed
aCCO 108.2 1 2 6 2010Vog/Alt:153
aCOC 107.9 2 1 3 2010Vog/Alt:153
aOCO 122.6 1 2 4 2010Vog/Alt:153
picture of Maleic Anhydride

Bond descriptions

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

Atom x (Å) y (Å) z (Å)
O1 0.0000 0.0000 0.9753
C2 0.0000 1.1206 0.1596
C3 0.0000 -1.1206 0.1596
O4 0.0000 2.2308 0.5936
O5 0.0000 -2.2308 0.5936
C6 0.0000 0.6654 -1.2539
C7 0.0000 -0.6654 -1.2539
H8 0.0000 1.3533 -2.0839
H9 0.0000 -1.3533 -2.0839

Atom - Atom Distances (Å)

  O1 C2 C3 O4 O5 C6 C7 H8 H9

Calculated geometries for C4H2O3 (Maleic Anhydride).
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squib reference DOI
2010Vog/Alt:153 N Vogt, EP Altova, NM Karasev "Equilibrium structure of maleic anhydride from gas-phase electron difraction (GED) and quantum-chemical studies" Journal of Molecular Structure 978 (2010) 153-157 10.1016/j.molstruc.2010.02.037

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