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 SiH2- (silicon dihydride anion)

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) cc-pVDZ cc-pVTZ aug-cc-pVTZ
Moller Plesset perturbation MP2=FULL -0.002111 -0.005607 -0.012295 -0.003598 -0.009949 -0.010442 -0.011558 -0.123868 -0.124279 -0.018474 -0.006271 -0.056034 -0.059587
MP3=FULL         -0.009690   -0.024105            
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) cc-pVDZ cc-pVTZ aug-cc-pVTZ