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Calculated Ionization Energy for C3H3 (cyclopropenyl radical)

20 09 09 14 00
Experimental Ionization Energy is 6.6 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
composite G4 6.222

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-pVDZ aug-cc-pVTZ daug-cc-pVTZ
hartree fock HF 3.769       5.136 5.132 5.245 5.251 5.238 5.082 5.231 5.237 5.205 5.269 5.217 5.088
density functional LSDA 5.131 6.675 6.675 6.586 6.490 6.498 6.689 6.695 6.693 6.488   6.635 6.694 6.749 6.719  
BLYP         5.854                      
B1B95 4.688 6.040 6.040 5.920 5.801 5.659 5.955 5.939 5.934 5.783   5.920 5.927 5.991 5.948  
B3LYP 4.816 6.199 6.199 6.108 5.974 5.976 6.164 6.153 6.148 5.954 6.167 6.111 6.147 6.213 6.172  
B3LYPultrafine         5.974                   6.171  
mPW1PW91 4.858 6.300 6.300 6.169 6.034 6.035 6.184 6.176 6.169 6.009   6.148 6.161      
M06-2X     6.146                          
PBEPBE 4.807 6.246 6.246 6.135 6.034 6.037 6.228 6.204 6.200 6.023   6.166 6.214      
PBE1PBE         6.008                      
TPSSh         5.994   6.142           6.128      
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-pVDZ aug-cc-pVTZ daug-cc-pVTZ
Moller Plesset perturbation MP2 3.496     5.446 5.141         5.469 5.586   5.783   5.847  
MP2=FULL 3.494     5.444           5.503     5.793   5.863  
ROMP2   12.268   12.193 14.887 15.359 15.567 15.499 15.925 16.744   15.359 17.462 15.718    
MP3         5.342                      
MP3=FULL         5.353   5.608                  
MP4         5.128       5.549              
B2PLYP                         6.008      
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-pVDZ aug-cc-pVTZ daug-cc-pVTZ
Quadratic configuration interaction QCISD   5.811 5.811 5.735 5.594 5.658 5.822 5.828 5.894 5.762   5.888 5.979      
Coupled Cluster CCD       5.588 5.379 5.420 5.631 5.656 5.719 5.610   5.633 5.857 5.818 5.908  
CCSD(T)=FULL         5.555                      
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-pVDZ aug-cc-pVTZ daug-cc-pVTZ

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 5.515   5.423 5.236 5.466 5.467      
density functional B3LYP 6.350 6.173 6.353 6.159 6.337 6.332      
Moller Plesset perturbation MP2 5.718   5.709   5.672 5.672      
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.