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

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

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

Calculated Ionization Energy for Ca (Calcium atom)

Experimental Ionization Energy is 6.11316 ± 0.00002 eV
Original data displayed. Press to display differences.
Differences displayed. Press to display original data.

Ionization Energies in eV
Methods with predefined basis sets
semi-empirical PM6  
composite G1 6.190
G2MP2 6.208
G2 6.173
G3B3 6.196
G3MP2 6.265
G4 6.065

Ionization Energies in eV
Methods with standard basis sets
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) TZVP cc-pVDZ cc-pVTZ aug-cc-pVTZ
hartree fock HF 4.014 5.118 5.108 5.128 5.122 5.122 5.122 5.119 5.119 5.119 5.119      
density functional LSDA 5.937 6.133 6.615 6.670 6.638 6.638 6.638 6.648 6.648 6.635        
SVWN                     6.633      
BLYP 5.284 6.103 6.063 6.092 6.062 6.062 6.062 6.070 6.070 6.061        
B1B95     5.885 226.304     5.908 5.911 5.911          
B3LYP 5.352   6.148 6.179 6.151 6.151 6.150 6.156 6.156 6.148 6.146      
B3PW91 5.220 6.023 5.983 6.032 6.005 6.005 6.005 6.006 6.006 6.004        
mPW1PW91 5.168 6.012 5.973 6.011 5.983 5.983 5.983 5.983 5.983 5.983        
M06-2X     6.266                      
PBEPBE 5.298 6.113 6.068 6.111 6.079 6.079 6.078 6.083 6.083 6.077        
PBE1PBE         6.003                  
TPSSh         5.978   5.978     5.979     5.964  
wB97X-D     6.017   6.074   6.074   6.072   6.061 6.074 6.058  
B97D3   6.576     6.549   6.549   6.543          
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) TZVP cc-pVDZ cc-pVTZ aug-cc-pVTZ
Moller Plesset perturbation MP2 4.441 5.499 5.595 5.511 5.659 5.659 5.660 5.779 5.779 5.796 5.520      
MP2=FULL 4.445 5.504 5.631 5.511 5.659 5.659 5.660 5.782 5.782 5.796        
MP3             5.812              
MP3=FULL         5.812   5.812              
MP4   5.782     5.871       5.955          
B2PLYP                         5.954  
Configuration interaction CID   5.830     5.858                  
CISD   5.831     5.865                  
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) TZVP cc-pVDZ cc-pVTZ aug-cc-pVTZ
Quadratic configuration interaction QCISD   5.831   5.816 5.884 5.884 5.885 5.935 5.935 5.927        
QCISD(T)         5.897                  
Coupled Cluster CCD   5.830   5.815 5.876 5.876 5.877 5.917 5.917 5.914        
CCSD         5.884                  
CCSD(T)         5.897                  
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) TZVP cc-pVDZ cc-pVTZ aug-cc-pVTZ

Ionization Energies in eV
Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
hartree fock HF 5.295   5.295   5.311 5.153
density functional B3LYP 6.109   6.109   6.439 6.208
Moller Plesset perturbation MP2 5.694   5.694   5.690 5.888
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.