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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 CN atoms 1 and 2

For CN (Cyano radical)
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) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pCVDZ cc-pCVTZ cc-pCVQZ daug-cc-pVDZ daug-cc-pVTZ
Moller Plesset perturbation MP2=FULL 0.0001 0.0002 0.0002 0.0002 0.0007 0.0007 0.0007 0.0006 0.0006 0.0020 0.0013 0.0006 0.0004 0.0021 0.0016 0.0005 0.0028 0.0017 0.0005 0.0012 0.0015 0.0005 0.0029
MP3=FULL         0.0007   0.0007       0.0014 0.0005 0.0004 0.0024         0.0005 0.0012 0.0016 0.0005 0.0034
MP4=FULL   0.0001     0.0007       0.0006   0.0014   0.0004 0.0024   0.0005 0.0033   0.0005 0.0013 0.0016 0.0005 0.0034
B2PLYP=FULL 0.0000 0.0000 0.0000 0.0000 0.0003 0.0003 0.0003 0.0003 0.0003 0.0009 0.0007 0.0002 0.0002 0.0012   0.0002 0.0016   0.0002 0.0006 0.0008 0.0002 0.0017
Coupled Cluster CCSD=FULL         0.0010     0.0003   0.0030 0.0024 0.0009 0.0006 0.0038 0.0029 0.0007 0.0052 0.0030 0.0008 0.0022 0.0028 0.0007 0.0054
CCSD(T)=FULL         0.0010           0.0024 0.0008 0.0005 0.0037 0.0028 0.0007 0.0053 0.0028 0.0006 0.0020 0.0025 0.0007 0.0054
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pCVDZ cc-pCVTZ cc-pCVQZ daug-cc-pVDZ daug-cc-pVTZ

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