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Calculated Ionization Energy for C3 (carbon trimer)

Experimental Ionization Energy is 13 ± 0.1 eV
Please note! These calculated ionizataion energies have the vibrational zero-point energy (zpe) included, but the zpe has NOT been scaled. Click on an entry for more details, including the ionization energy with a scaled zpe.
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  

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) 6-311+G(3df,2p) TZVP Def2TZVPP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ
hartree fock HF 10.453 12.658 12.658 12.491 12.538             11.728 11.578            
density functional LSDA 10.190 12.124 12.124 11.968 12.073 12.073 12.296 12.319 12.319 12.118       12.239 12.318        
BLYP 9.577 11.405 11.405 11.263 11.349 11.349 11.611 11.592 11.592 11.403       11.523 11.617        
B1B95 10.358 12.158 12.158 11.976 12.048 12.048 12.231 12.235 12.235 12.074       12.191 12.227        
B3LYP         12.208     12.393 12.393     12.419 11.849   12.404 12.409   12.421 12.415
B3LYPultrafine                                   12.421  
B3PW91   12.249 12.249 12.040 12.103 12.103 12.273 12.285 12.285 12.123       12.240 12.277        
mPW1PW91 10.331 12.245 12.245 12.046 12.122 12.122 12.300 12.302 12.302 12.137       12.257 12.295        
M06-2X     12.738   12.386                            
PBEPBE 9.669 11.539 11.539 11.363 11.446 11.446 11.669 11.649 11.647 11.479     11.682 11.601 11.671        
PBE1PBE         12.076                            
HSEh1PBE   12.176     12.056   12.239               12.247        
TPSSh         11.961   12.119     11.978         12.122        
wB97X-D     12.497   11.526   11.697   11.696     11.722   11.697 11.640     11.643  
B97D3   12.659     11.412   11.612   11.586   11.595       11.600     11.610  
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP Def2TZVPP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ
Moller Plesset perturbation MP2 8.086 10.684   10.489 11.041 10.816 11.037 11.297 11.073 11.058   11.060 11.476 11.020 11.262   11.166 11.312  
MP2=FULL 8.085 10.686   10.490 10.822 10.822 11.042 11.082 11.082 11.069       11.023 11.277     11.327  
Configuration interaction CID   11.488   11.357 11.892     12.317                      
CISD   11.371   11.236 11.795     12.210                      
Coupled Cluster CCD   11.242     11.726 11.726   12.179 12.179 12.193       12.106 12.234        
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP Def2TZVPP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ

Ionization Energies in eV
Methods with effective core potentials (select basis sets)
daug-cc-pVDZ daug-cc-pVTZ daug-cc-pVQZ Sadlej_pVTZ CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
hartree fock HF         12.576 12.628 12.585 12.674 12.640 12.637
density functional B3LYP         12.199 12.230 12.220 12.282    
Moller Plesset perturbation MP2         10.658 10.970 10.714 11.027 10.665 10.666
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.