National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 22May 2022
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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IV.A.1. (XIV.A.)

Reaction Enthalpy Comparison

Enter species formula
Reactants Products
Formula Name CAS no. Formula Name CAS no.
Rules for chemical formulas
Enter a sequence of element symbols followed by numbers to specify the amounts of desired elements (e.g., C6H6).
Elements may be in any order.
If only one of a given atom is desired, you may omit the number after the element symbol.
Parentheses may be used to group atoms.
Multiple specifications for an atom will be added. This means that CH3(CH2)4CH3 will be treated the same as C6H14.
The reaction enthalpy pages only work with neutral species in their ground electronic state.