National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 18October 2016
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

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XVII.C.1. (III.D.6.)

Calculated Ionization Energy for I (Iodine atom)

Experimental Ionization Energy is 10.45126 eV
Original data displayed. Press to display differences.
Differences displayed. Press to display original data.

Ionization Energies in eV
Methods with predefined basis sets

Ionization Energies in eV
Methods with standard basis sets
3-21G 3-21G* 6-31G* 6-311G* 6-311G**
density functional wB97X-D   10.455      
B97D3 10.272        
3-21G 3-21G* 6-31G* 6-311G* 6-311G**
Moller Plesset perturbation MP2     10.117 10.117  
3-21G 3-21G* 6-31G* 6-311G* 6-311G**
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.