return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Calculated > Energy > Correlation > Full vs Frozen core energies

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

For CBr2 (dibromomethylene)

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) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ
Moller Plesset perturbation MP2=FULL -0.000373 -0.008201 -0.022076 -0.022340 -0.059208 -0.059208 -0.060822 -0.807302 -0.807302 -0.173763 -0.905021 -0.147505 -0.017832 -0.103116 -0.022262 -0.113203
MP3=FULL         -0.055247   -0.056813       -0.804427 -0.126511 -0.015521 -0.090263    
MP4=FULL   -0.007813     -0.057384       -0.760842   -0.852849   -0.016897 -0.099519 -0.021350 -0.109332
B2PLYP=FULL -0.000117 -0.002481 -0.006736 -0.006569 -0.018104 -0.018104 -0.018577 -0.236896 -0.236896 -0.053349 -0.265636 -0.043701 -0.005479 -0.030870 -0.006819 -0.033756
Quadratic configuration interaction QCISD(T)=FULL         -0.056703           -0.838632   -0.016459 -0.096375 -0.020762 -0.105935
Coupled Cluster CCSD=FULL         -0.055470         -0.160884 -0.829550 -0.131636 -0.015654 -0.092925 -0.019745 -0.102408
CCSD(T)=FULL         -0.056682           -0.838341 -0.135328 -0.016443 -0.096215 -0.020724 -0.105769
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 cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ