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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 KCl atoms 1 and 2

For KCl (Potassium Chloride)
Bond length differences (full - frozen) in Å. Mouse over a difference for the bond length with full correlation.
Methods with standard basis sets
3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p)
Moller Plesset perturbation MP2=FULL 0.0295 0.0936 0.0002 0.0003 0.0002 0.0003 0.0045 0.0024 0.0024
MP3=FULL       -0.0093   -0.0169      
Coupled Cluster CCSD(T)=FULL       0.0001          
3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p)

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