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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Compare Barriers to Internal Rotation

Which torsion in CH3COCH2CH3?

picture of 2-Butanone
Please choose which four atoms describe the torsional coordinate.
choose Atom1 Atom2 Atom3 Atom4 Type of Rotor
torsion 1 1 2 3 4 CH2CH3
torsion 2 9 4 3 2 CH3
torsion 3 6 1 2 3 CH3