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 C4H5NO (Isoxazole, 5-methyl-)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
Rotational Constants from
Calculated rotational constants for C4H5NO (Isoxazole, 5-methyl-).

Point Group C1

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 1.505 1 5 1995Kuchitsu(II/23) to methyl
rCC 1.362 5 10 1995Kuchitsu(II/23) !assumed
rCC 1.427 8 10 1995Kuchitsu(II/23) !assumed, opp O
rCN 1.310 7 8 1995Kuchitsu(II/23) !assumed
rNO 1.403 6 7 1995Kuchitsu(II/23) !assumed
rCO 1.342 5 6 1995Kuchitsu(II/23) !assumed
aCCO 116 1 5 6 1995Kuchitsu(II/23) !assumed
aCCC 102.7 1 5 10 1995Kuchitsu(II/23) !assumed
aCCN 112.5 7 8 10 1995Kuchitsu(II/23) !assumed
aCNO 105.2 6 7 8 1995Kuchitsu(II/23) !assumed
aCON 108.8 5 6 7 1995Kuchitsu(II/23) !assumed
aCCO 110.7 6 5 10 1995Kuchitsu(II/23) !assumed
picture of Isoxazole, 5-methyl-

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
H-C 5
C-C 2
C=C 1
C=N 1
C-O 1
N-O 1

Atom x (Å) y (Å) z (Å)

Atom - Atom Distances (Å)


Calculated geometries for C4H5NO (Isoxazole, 5-methyl-).
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squib reference DOI
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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