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Calculated Proton Affinity

20 10 26 10 44
Name Species   Species Name
2H-pyrrole C4H5N C4H6N+ pyrrole, alpha-protonated

Bonding changes

Bond type H-N gained 1
Proton Affinities (kJ/mol)
Proton Affinities in kJ/mol
Methods with predefined basis sets
composite G3B3 926

Proton Affinities in kJ/mol
Methods with standard basis sets
3-21G* 6-31G* 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ aug-cc-pVTZ daug-cc-pVTZ
hartree fock HF   958                   960
density functional BLYP   942                    
B3LYP           957         937  
M06-2X 959                      
TPSSh   948 942     960       946    
wB97X-D 979 951 945   949     947 949 950 947  
B97D3             947          
3-21G* 6-31G* 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ aug-cc-pVTZ daug-cc-pVTZ
Moller Plesset perturbation MP2   922   910                
MP3     747                  
MP3=FULL   934                    
3-21G* 6-31G* 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ aug-cc-pVTZ daug-cc-pVTZ

Proton Affinities in kJ/mol
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                 961
density functional B3LYP                 939
PBEPBE                 932
Moller Plesset perturbation MP2                 917
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.