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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 BeH- atoms 1 and 2

For BeH- (berylium monohydride anion)
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) cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVQZ
Moller Plesset perturbation MP2=FULL -0.0000 0.0002 0.0002 0.0001 0.0044 0.0019 0.0014 0.0134 0.0023 0.0033 0.0012 0.0135 0.0063 0.0031 0.0068
MP3=FULL         -0.0015   0.0562                
Coupled Cluster CCSD(T)=FULL         0.0020               0.0072   0.0077
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-pVQZ

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