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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Calculated Proton Affinity

Name Species   Species Name
Helium atom He HeH+ Helium hydride cation

Bonding changes

Bond type H-He gained 1
Proton Affinities (kJ/mol)
Proton Affinities in kJ/mol
Methods with predefined basis sets

Proton Affinities in kJ/mol
Methods with standard basis sets
For descriptions of the methods (AM1, HF, MP2, ...) and basis sets (3-21G, 3-21G*, 6-31G, ...) see the glossary in section I.C. Predefined means the basis set used is determined by the method.