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 NaI atoms 1 and 2

For NaI (Sodium Iodide)
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* 6-311G*
Moller Plesset perturbation MP2=FULL 0.0051 -0.0010 0.0045 0.0064
MP3=FULL       0.0050
MP4=FULL   -0.0010   0.0066
B2PLYP=FULL 0.0015 -0.0004 0.0019 0.0026
Quadratic configuration interaction QCISD(T)=FULL       0.0062
Coupled Cluster CCSD=FULL       0.0050
CCSD(T)=FULL       0.0061
STO-3G 3-21G 3-21G* 6-311G*

nai.gif