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Energy differences between frozen core and all electrons correlated.
MP2, MP3, MP4, B2PLYP, CCSD, and CCSD(T)

For Li3 (Lithium trimer)

Energies in Hartree
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
Moller Plesset perturbation MP2=FULL -0.001384 -0.001078 -0.001078 -0.001128   -0.002408 -0.002584   -0.039358 -0.009639 -0.038783 -0.001363 -0.035993 -0.050227 -0.001809 -0.037698 -0.052232
MP3=FULL         -0.002416   -0.002600       -0.043781 -0.001400 -0.041421        
MP4=FULL   -0.001094     -0.002433       -0.046121     -0.001410 -0.042422   -0.001848 -0.044268  
B2PLYP=FULL -0.000491 -0.000390 -0.000390 -0.000398 -0.000810 -0.000810 -0.000869 -0.011878 -0.011878 -0.003063 -0.011704 -0.000482 -0.011004   -0.000624 -0.011534  
Quadratic configuration interaction QCISD(T)=FULL         -0.002444             -0.001418 -0.042584   -0.001850 -0.044424  
Coupled Cluster CCSD=FULL         -0.002325           -0.044566 -0.001337 -0.042152 -0.057693 -0.001747 -0.043954 -0.059946
CCSD(T)=FULL         -0.002435           -0.044748 -0.001408 -0.042552 -0.058339 -0.001838 -0.044388 -0.060599
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