National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
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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Tautomer energy comparison

using model chemistry: MP2/cc-pV(T+d)Z

formula sketch Energy (kJ mol-1) Name difference
A B calculated experiment A B
C3H4 sketch of allene sketch of propyne 19 7 allene propyne 12
C4H6 sketch of 1,2-Butadiene sketch of 1,3-Butadiene 50 51 1,2-Butadiene 1,3-Butadiene -1
C4H6 sketch of 1,2-Butadiene sketch of 2-Butyne 31 17 1,2-Butadiene 2-Butyne 14
C4H6 sketch of Cyclobutene sketch of 1,3-Butadiene 43 49 Cyclobutene 1,3-Butadiene -6
C4H6 sketch of 1-Methylcyclopropene sketch of 1,2-Butadiene 66 82 1-Methylcyclopropene 1,2-Butadiene -17
C4H6 sketch of Methylenecyclopropane sketch of 1-Methylcyclopropene -41 -42 Methylenecyclopropane 1-Methylcyclopropene 0