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 C3H3NO (Isoxazole)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
0.32644 0.31939 0.16134
Rotational Constants from 1975Sti:2560
Calculated rotational constants for C3H3NO (Isoxazole).

Point Group Cs

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 1.075 1 2 1975Sti:2560
rCO 1.344 2 5 1975Sti:2560
rNO 1.399 5 8 1975Sti:2560
rCN 1.309 7 8 1975Sti:2560
rCH 1.077 6 7 1975Sti:2560
rCC 1.425 4 7 1975Sti:2560
rCH 1.074 3 4 1975Sti:2560
rCC 1.356 2 4 1975Sti:2560
aHCC 133.4 1 2 4 1975Sti:2560
aCCO 110.6 4 2 5 1975Sti:2560
aCON 108.8 2 5 8 1975Sti:2560
aCNO 105.3 5 8 7 1975Sti:2560
aCCN 112.3 4 7 8 1975Sti:2560
aHCN 118.6 6 7 8 1975Sti:2560
aCCC 103 2 4 7 1975Sti:2560
aHCC 128.5 2 4 3 1975Sti:2560 going away from O
picture of Isoxazole

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
H-C 3
C-O 1
N-O 1
C=N 1
C-C 1
C=C 1

Atom x (Å) y (Å) z (Å)
H1 -0.1778 2.1863 0.0000
C2 0.0000 1.1262 0.0000
H3 2.1494 0.6954 0.0000
C4 1.1258 0.3703 0.0000
O5 -1.0939 0.3453 0.0000
H6 1.1568 -1.8937 0.0000
C7 0.6179 -0.9612 0.0000
N8 -0.6914 -0.9946 0.0000

Atom - Atom Distances (Å)

  H1 C2 H3 C4 O5 H6 C7 N8

Calculated geometries for C3H3NO (Isoxazole).
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squib reference DOI
1975Sti:2560 Stiefvater, Otto, The complete structure of isoxazole from naturally occurring isotopic forms by double resonance modulated microwave spectroscopy, J. of Chem. Phys., Vol. 63, #6, pgs. 2560-2569 10.1063/1.431647

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