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Calculated Ionization Energy for C2H3 (vinyl)

Experimental Ionization Energy is 8.25 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.
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Ionization Energies in eV
Methods with predefined basis sets
composite G2 8.360
G3 8.477
G3B3 8.465
G4 8.469
CBS-Q 8.473

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         8.508 8.421 8.511 8.538 8.426 8.280   8.425 8.376 8.444 8.370 8.262 8.461 8.373 8.264
ROHF 6.738 8.053 8.053 7.985 7.966 7.943 8.050 8.056 8.023 7.893       8.013 8.009 8.016 8.054 8.019 8.019
density functional LSDA         8.780 8.716 8.880 8.914 8.824 8.626       8.768 8.805   8.862 8.818  
BLYP         8.373 8.314 8.513 8.515 8.437 8.235       8.379 8.442        
B1B95         8.385 8.333 8.471 8.642 8.400 8.227       8.367 8.346   8.413 8.358  
B3LYP         8.612 8.546 8.710 8.724 8.637 8.451   8.675 8.642 8.599 8.627 8.660 8.690 8.642 8.668
B3LYPultrafine         8.612                            
B3PW91         8.660 8.588 8.713 8.738 8.644 8.487       8.621 8.616        
mPW1PW91         8.641 8.567 8.697 8.715 8.640 8.485       8.599 8.591        
M06-2X     8.892   8.455                            
PBEPBE         8.481 8.411 8.579 8.588 8.498 8.325     8.509 8.458 8.491   8.551    
PBE1PBE         8.613                            
HSEh1PBE         8.615   8.672               8.574        
TPSSh         8.640   8.700     8.471         8.610        
wB97X-D         8.553   8.609   8.532     8.551   8.609 8.485     8.495  
B97D3         8.517   8.603   8.534   8.537       8.521     8.542  
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 6.308     8.002 7.781 7.793 7.949 7.932 7.904 7.775   7.899 8.022 7.920 8.008   8.040 8.041  
MP2=FULL 6.304     8.000 7.778 7.793 7.948 7.932 7.902 7.779       7.918 7.999        
ROMP2 9.677 12.442 12.442 12.366 14.238 14.704 14.865 14.667           14.698          
MP3         7.968                            
MP3=FULL         7.965   8.144                        
MP4         7.885       8.033                    
B2PLYP         8.358                   8.433        
Configuration interaction CID         8.071     8.204                      
CISD         8.145     8.272                      
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
Quadratic configuration interaction QCISD         8.236 8.263 8.392 8.373 8.363 8.246       8.396 8.445        
QCISD(T)         8.192                 8.352 8.417   8.479 8.464  
Coupled Cluster CCD         8.022 8.051 8.189 8.167 8.158 8.037       8.178 8.253   8.293    
CCSD         8.242                            
CCSD(T)         8.196                 8.350 8.581   8.476 8.459  
CCSD(T)=FULL         8.186                   8.402        
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               8.541    
density functional B3LYP               8.772    
Moller Plesset perturbation MP2         8.142 7.921 8.059 7.897 8.082 8.076
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.