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XVII.C.1.

Calculated Ionization Energy for BeO (beryllium oxide)

Experimental Ionization Energy is 10.1 ± 0.4 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 PM3  
PM6  
composite G3 9.779
G3B3 9.831
G4 9.925
CBS-Q 9.904

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 cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z
hartree fock HF 6.077 7.447 7.447 7.691 7.565 7.565 7.724 7.719 7.719 7.542 7.681 7.630 7.636 7.660 7.684 7.668 7.676 7.636
density functional LSDA 9.667 10.841 10.841 10.989 10.845 10.845 11.016 11.016 11.016 10.850   10.900 10.977   11.003 11.012   10.977
SVWN   10.841     10.845   11.016                      
BLYP 8.702 9.925 9.925 10.029 9.885 9.885 10.068 10.054 10.054 9.881   9.954 10.015          
B1B95 8.471 9.627 9.627 9.807 9.564 9.637 9.804 9.804 9.804 9.633   9.708 9.660   9.706     9.625
B3LYP 8.557 9.768 9.768 9.911 9.764 9.764 9.944 9.934 9.934 9.757 9.943 9.830 9.887 9.920 9.922 9.928 9.940 9.887
B3LYPultrafine         9.764             9.830 9.888   9.922 9.928    
B3PW91 8.510 9.687 9.687 9.849 9.684 9.684 9.841 9.838 9.838 9.670                
mPW1PW91 8.390 9.561 9.583 9.743 9.558 9.558 9.723 9.716 9.736 9.562   9.650 9.665         9.665
M06-2X         9.604                          
PBEPBE 8.805 10.002 10.002 10.113 9.953 9.953 10.120 10.107 10.107 9.942 10.127 10.023 10.054   10.103 10.091   10.054
PBEPBEultrafine         9.953             10.023 10.054   10.103 10.091    
PBE1PBE         9.573                          
HSEh1PBE         9.570                          
TPSSh             9.768                      
Moller Plesset perturbation MP2 8.400 9.689 9.689 9.871 9.849 9.849 10.035 9.966 9.966 9.985 9.957 9.875 10.109 10.219 10.086 10.205 10.275 10.109
MP2=FULL 8.402 9.694 9.694 9.876 9.869 9.869 10.056 9.987 9.987 10.036   9.889 10.140 10.265   10.255    
MP3         9.120                          
MP3=FULL         9.144   9.321                      
MP4   10.519     9.963       10.060       10.134          
B2PLYP         9.759                          
Configuration interaction CID   8.845 8.845 9.072 9.047     9.154                    
CISD   8.967 8.967 9.169 9.113     9.223                    
Quadratic configuration interaction QCISD   9.789 9.789 9.913 9.657 9.657 9.777 9.707 9.706 9.663 9.647 9.693 9.700   9.768 9.757   9.700
QCISD(T)         9.422             9.464 9.782   9.665 9.857    
Coupled Cluster CCD   9.025 9.025 9.256 9.248 9.248 9.428 9.356 9.356 9.367 9.311 9.259 9.453   9.449 9.535    
CCSD         9.333                          
CCSD=FULL         9.354           9.402 9.373 9.556 9.659 9.566 9.655 9.705  
CCSD(T)         9.529             9.564 9.764   9.723 9.842   9.764
CCSD(T)=FULL         9.548           9.614 9.578 9.797 9.906 9.764 9.899 9.954  

Ionization Energies in eV
Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
hartree fock HF 7.912 7.709 7.992 7.754 7.776 8.214
density functional B3LYP 9.904 9.673 9.939 9.705 10.027 10.288
Moller Plesset perturbation MP2 10.071 9.990 10.179 10.059 10.053 10.213
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.