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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 CH atoms 1 and 2

For CH (Methylidyne)
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 daug-cc-pVDZ daug-cc-pVTZ
Moller Plesset perturbation MP2=FULL 0.0000 0.0001 0.0001 0.0001 0.0010 0.0010 0.0009 0.0004 0.0009 0.0018 0.0018 0.0007 0.0008 0.0071 0.0029 0.0010 0.0112 0.0027 0.0010 0.0104
MP3=FULL         -0.0003   -0.0004                          
B2PLYP=FULL 0.0000 0.0000 0.0000 0.0000 0.0001 0.0003 0.0003 0.0006 0.0002 0.0006 0.0005 0.0002 0.0003 0.0020   0.0003 0.0035   0.0003 0.0033
Quadratic configuration interaction QCISD(T)=FULL         0.0009   0.0018       0.0023   0.0015 0.0093   0.0011 0.0118   0.0011 0.0114
Coupled Cluster CCSD=FULL         0.0005         0.0026 0.0020 0.0009 0.0010 0.0087 0.0039 0.0011 0.0123 0.0031 0.0010 0.0115
CCSD(T)=FULL         0.0004           0.0022 0.0013 0.0015 0.0093 0.0036 0.0011 0.0119 0.0034 0.0011 0.0114
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 daug-cc-pVDZ daug-cc-pVTZ

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