National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
NIST Standard Reference Database 101
IIntroduction
IIExperimental data
IIICalculated data
IVData comparisons
VCost comparisons
VIInput and output files
VIITutorials and Units
VIIILinks to other sites
IXFeedback
XOlder CCCBDB versions
XIIGeometries
XIII Vibrations
XIVReaction data
XVEntropy data
XVIBibliographic data
XVIIIon data
XVIIIBad calculations
XIXIndex of properties
XXH-bond dimers
XXIOddities

NIST policy on privacy, security, and accessibility.

Please rate our products
© 2013 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce.

Please send questions, comments, corrections, additions and suggestions to cccbdb@nist.gov.

return to home page

IV.A.4.b.

Tautomer energy comparison

using model chemistry: QCISD/6-31+G**

formula sketch Energy (kJ mol-1) Name difference
A B calculated experiment A B
C3H4 sketch of allene sketch of propyne 2 7 allene propyne -4
C4H6 sketch of Cyclobutene sketch of 1,3-Butadiene 56 49 Cyclobutene 1,3-Butadiene 6
C4H6 sketch of Cyclobutene sketch of 1,3-Butadiene 45 49 Cyclobutene 1,3-Butadiene -5
C4H6 sketch of 1,2-Butadiene sketch of 1,3-Butadiene 52 51 1,2-Butadiene 1,3-Butadiene 1
C4H6 sketch of 1,2-Butadiene sketch of 1,3-Butadiene 41 51 1,2-Butadiene 1,3-Butadiene -10
C4H6 sketch of 1,2-Butadiene sketch of 1-Butyne -6 -3 1,2-Butadiene 1-Butyne -3
C4H6 sketch of 1,2-Butadiene sketch of 2-Butyne 13 17 1,2-Butadiene 2-Butyne -4
C3H6O sketch of Oxetane sketch of Propanal 113 110 Oxetane Propanal 3
C3H6O sketch of Oxetane sketch of Propanal 114 110 Oxetane Propanal 4
C4H8 sketch of cyclobutane sketch of 1-Butene 30 33 cyclobutane 1-Butene -2
C4H8 sketch of cyclobutane sketch of 1-Butene 30 33 cyclobutane 1-Butene -2
C4H8 sketch of cyclobutane sketch of 1-Butene 30 33 cyclobutane 1-Butene -2
C4H8 sketch of cyclobutane sketch of 1-Butene 30 33 cyclobutane 1-Butene -2
C5H8 sketch of 1,2-Butadiene, 3-methyl- sketch of 1,3-Butadiene, 2-methyl- 51 52 1,2-Butadiene, 3-methyl- 1,3-Butadiene, 2-methyl- -1
C5H8 sketch of 1,3-Pentadiene, (E)- sketch of 1,4-Pentadiene -24 -25 1,3-Pentadiene, (E)- 1,4-Pentadiene 1