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Bond Length differences between FULL (all electrons correlated) and FROZEN core

Such as MP2=Frozen and MP2=Full
17 10 27 16 27

For CaH atoms 1 and 2

For CaH (Calcium monohydride)
Bond length differences (full - frozen) in Å. Mouse over a difference for the bond length with full correlation.
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
Moller Plesset perturbation MP2=FULL -0.0026 -0.0008 -0.0016 -0.0000 0.0000 -0.0000 -0.0000 -0.0084 0.0009 -0.0001 0.0049 0.0317 0.0294 0.0516
MP3=FULL         -0.0015   0.0008              
MP4=FULL   -0.0007     -0.0000       0.0009     0.0337 0.0277  
Coupled Cluster CCSD=FULL         -0.0000           0.0056 0.0328 0.0253 0.0472
CCSD(T)=FULL         -0.0000           0.0054 0.0331 0.0266 0.0494
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

cahq1.gif