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

For AlH3+ (aluminum trihydride cation)

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 cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ
Moller Plesset perturbation MP2=FULL -0.007773 -0.004447 -0.009231 -0.003363 -0.008174 -0.008546 -0.009698 -0.124132 -0.124586 -0.013904 -0.004794 -0.065321 -0.044525 -0.006717 -0.071984 -0.057507
MP3=FULL         -0.008198   -0.010522                  
Coupled Cluster CCSD(T)=FULL         -0.008483           -0.004858 -0.067357 -0.047108 -0.006888 -0.074092 -0.059609
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 cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ