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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 BSi atoms 1 and 2

For BSi (Boron silicide)
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
Moller Plesset perturbation MP2=FULL 0.0002 0.0002 0.0011 0.0002 0.0024 0.0024 0.0021 0.0014 0.0014 0.0083 0.0045 0.0010 0.0018 0.0083 0.0082 0.0023 0.0120 0.0095
MP3=FULL         0.0022   0.0019       0.0043 0.0009 0.0018 0.0082        
MP4=FULL   -0.0001     0.0028       0.0016   -0.0410   0.0021 0.0100   0.0027 0.0177  
B2PLYP=FULL 0.0004 0.0001 0.0003 0.0001 0.0010 0.0010 0.0010 0.0006 0.0006 0.0030 0.0018 0.0005 0.0006 0.0029   0.0007 0.0042  
Quadratic configuration interaction QCISD(T)=FULL         0.0036           0.0063   0.0026 0.0116   0.0033 0.0170  
Coupled Cluster CCSD=FULL         0.0031         0.0099 0.0061 0.0015 0.0027 0.0103 0.0101 0.0026 0.0147 0.0116
CCSD(T)=FULL         0.0031           0.0059 0.0015 0.0022 0.0103 0.0101 0.0042 0.0167 0.0124
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

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