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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 HBr atoms 1 and 2

For HBr (hydrogen bromide)
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 0.0000 -0.0001 0.0007 0.0003 0.0016 0.0017 0.0037 0.0027 0.0098 0.0035 -0.0009 0.0009 0.0054 0.0032 0.0014 0.0093 0.0044 0.0015 0.0068
MP3=FULL         -0.0051   -0.0008       0.0028 -0.0008 0.0009 0.0046         0.0014 0.0062
MP4=FULL   -0.0000     0.0005       0.0021   0.0030   0.0010 0.0039   0.0014 0.0073   0.0015 0.0063
B2PLYP=FULL 0.0000 -0.0000 -0.0000 0.0002 0.0044 0.0005 0.0004 0.0003 0.0008 0.0010 0.0011 -0.0002 0.0003 0.0018   0.0005 0.0028   0.0005 0.0019
Quadratic configuration interaction QCISD(T)=FULL         0.0005           0.0030   0.0010 0.0042   0.0015 0.0072   0.0015 0.0062
Coupled Cluster CCSD=FULL         0.0005         0.0091 0.0031 -0.0005 0.0010 0.0049 0.0040 0.0014 0.0085 0.0047 0.0015 0.0065
CCSD(T)=FULL         0.0007           0.0028 -0.0006 0.0010 0.0035 0.0036 0.0014 0.0073 0.0041 0.0015 0.0062
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

hbrq1.gif