return to home page Computational Chemistry Comparison and Benchmark DataBase Release 20 (August 2019) 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 KH atoms 1 and 2

For KH (Potassium hydride)
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 Def2TZVPP
Moller Plesset perturbation MP2=FULL -0.0600 0.0007 0.0035 -0.0000 -0.0021 0.0000 0.0000 -0.0003 0.0020 0.0002 0.0023 0.0139 0.0618
MP3=FULL         0.0051   -0.0003       0.0015 0.0144 0.0578
MP4=FULL   0.0012     0.0000       0.0018   0.0021   0.0602
B2PLYP=FULL 0.0000 -0.0021 0.0013 -0.0000 -0.0026 0.0000 -0.0033 0.0003 0.0005 0.0001 0.0007 0.0048 0.0210
Quadratic configuration interaction QCISD(T)=FULL         0.0000           0.0020   0.0577
Coupled Cluster CCSD=FULL         0.0000         0.0002 0.0018 0.0142 0.0547
CCSD(T)=FULL         0.0000           0.0020 0.0144 0.0576
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 Def2TZVPP

khq1.gif