return to home page Computational Chemistry Comparison and Benchmark DataBase Release 19 (April 2018) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Home > Ions > Energy > Calculated Ionization Energy OR Calculated > Energy > Ion > Calculated Ionization Energy

Calculated Ionization Energy for CH3NH3 (methyl ammonium radical)

Experimental Ionization Energy is 4.3 ± 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 AM1  
PM3  
PM6  
composite G3B3 4.949
G4 4.951

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         2.395   3.341 2.738 2.735     2.935 2.946 2.471 2.854 3.113 3.615 3.612 3.612
density functional LSDA   3.724 3.724 4.049 4.065 4.060 4.909 4.577 4.568 4.024       4.350 4.645   5.052 5.037  
BLYP 2.188     3.544 3.573 3.551 4.334 3.989 3.982 3.511       3.802 4.062        
B1B95       3.153 3.201 2.857 4.025 3.638 3.630 3.141       3.415 3.708     4.182  
B3LYP 2.339     3.459 3.495 3.470 4.305 3.934 3.927 3.434   4.099 4.090 3.729 4.012 4.185 4.475 4.458 4.457
B3LYPultrafine         3.495                         4.458  
B3PW91       3.408     4.197 3.853 3.846         3.652 3.917        
mPW1PW91       3.347     4.154 3.796 3.788         3.594 3.859        
PBEPBE       3.578 3.638 3.618 4.362 4.017 4.010       4.163 3.832 4.087        
TPSSh             4.064               3.794        
wB97X-D             3.918   3.560     3.680   3.918 3.608     4.088  
B97D3             3.942   3.700   3.974       3.733     4.107  
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   2.010 2.010 2.525 2.612 2.663 3.880 3.358 3.449 2.687   3.639 3.729 3.144 3.648 3.874 4.158 4.167  
MP2=FULL   2.008 2.008 2.524 2.609 2.655 3.877 3.355 3.444 2.673       3.139 3.633     4.159  
MP3         2.562                            
MP3=FULL         2.559   3.828                        
MP4   2.071     2.659       3.474                    
B2PLYP                             3.800        
Configuration interaction CID       2.446 2.501     3.160                      
CISD       2.486 2.543     3.170                      
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             3.842 3.329 3.417         3.160 3.588        
QCISD(T)                           3.223     4.211    
Coupled Cluster CCD   2.041 2.041 2.518 2.578 2.626 3.813 3.285 3.368 2.639       3.081 3.544   4.094    
CCSD(T)                           3.220 3.678   4.209    
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             2.913 2.881    
density functional B3LYP             4.080 4.049 3.361 3.359
Moller Plesset perturbation MP2             3.465 3.524    
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.