return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Comparisons > Geometry > Bonds, angles > Core correlation - bond length

Bond Length differences between FULL (all electrons correlated) and FROZEN core

Such as MP2=Frozen and MP2=Full
17 10 27 16 27

For BeH atoms 1 and 2

For BeH (beryllium monohydride)
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) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pCVDZ cc-pCVTZ
Moller Plesset perturbation MP2=FULL -0.0001 0.0002 -0.0003 -0.0004 0.0009 0.0001 0.0009 0.0011 0.0025 0.0021 0.0005 0.0006 0.0103 0.0052 0.0028 0.0235 0.0058 0.0011 0.0032
MP3=FULL         0.0006   0.0012       0.0011 0.0006 0.0111         0.0011 0.0038
MP4=FULL   0.0002     0.0006       0.0020     0.0007 0.0108   0.0026 0.0271   0.0011 0.0033
B2PLYP=FULL -0.0000 0.0001 0.0001 0.0000 0.0000 0.0003 0.0003 0.0001 0.0006 0.0014 0.0001 0.0002 0.0037   0.0012 0.0071   0.0003 0.0010
Quadratic configuration interaction QCISD(T)=FULL         0.0008   0.0010         0.0009 0.0113   0.0028 0.0277   0.0010  
Coupled Cluster CCSD=FULL         0.0007           0.0004 0.0007 0.0108 0.0059 0.0027 0.0277 0.0065 0.0011 0.0033
CCSD(T)=FULL         0.0008           0.0005 0.0010 0.0113 0.0057 0.0029 0.0277 0.0063 0.0010 0.0030
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pCVDZ cc-pCVTZ

behq1.gif