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Calculated Ionization Energy for I (Iodine atom)

20 09 09 14 00
Experimental Ionization Energy is 10.45126 eV
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Differences displayed. Press to display original data.

Ionization Energies in eV
Methods with predefined basis sets
semi-empirical PM3  

Ionization Energies in eV
Methods with standard basis sets
3-21G 3-21G* 6-31G* 6-311G*
hartree fock HF 9.425      
ROHF 9.429      
density functional BLYP 10.207      
B1B95 8.620      
B3LYP 10.427      
B3PW91 10.447      
mPW1PW91 10.414      
M06-2X   10.182    
PBEPBE 10.314      
wB97X-D   10.455    
B97D3 10.308      
3-21G 3-21G* 6-31G* 6-311G*
Moller Plesset perturbation MP2 9.574   10.117 10.117
MP2=FULL 9.569      
MP4 9.603      
Configuration interaction CID 9.601      
CISD 9.600      
3-21G 3-21G* 6-31G* 6-311G*
Quadratic configuration interaction QCISD 9.605      
Coupled Cluster CCD 9.605      
3-21G 3-21G* 6-31G* 6-311G*

Ionization Energies in eV
Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD cc-pVTZ-PP aug-cc-pVTZ-PP Def2TZVPP
hartree fock HF 9.660   9.660   9.693 9.756 9.574   9.551
ROHF             9.596   9.573
density functional LSDA             11.337   11.236
BLYP             10.460   10.295
B1B95             10.497   10.481
B3LYP 10.724   10.724   10.743 10.840 10.646   10.632
B3LYPultrafine             10.646   10.632
B3PW91             10.614   10.594
mPW1PW91             10.579   10.565
M06-2X             10.292   10.277
PBEPBE             10.514   10.506
PBEPBEultrafine             10.514   10.506
PBE1PBE             10.548   10.533
HSEh1PBE             10.577   10.561
TPSSh             10.555   10.542
wB97X-D             10.644   10.621
B97D3             10.493   10.619
Moller Plesset perturbation MP2 9.777   9.777   9.801 9.845 10.362   10.357
MP2=FULL             10.360   10.362
ROMP2             10.355   10.345
MP3             10.358   10.304
MP3=FULL             10.350   10.303
MP4             10.384   10.376
MP4=FULL             10.380   10.379
B2PLYP             10.503   10.491
B2PLYP=FULL             10.502   10.492
Configuration interaction CID             10.264   10.160
CISD             10.261   10.159
Quadratic configuration interaction QCISD             10.348   10.321
QCISD(T)             10.380   10.359
QCISD(T)=FULL             10.374   10.361
Coupled Cluster CCD             10.349   10.321
CCSD             10.348   10.321
CCSD=FULL             10.340   10.319
CCSD(T)             10.380   10.359
CCSD(T)=FULL             10.374   10.361
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.