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: Home > Geometry > Experimental > Same bond/angle many molecules OR Comparisons > Geometry > Bonds, angles > Same bond/angle many molecules

Comparison of experiment and theory for rSiI

18 10 23 14 56
Species with coordinate rSiI
Species Name
SiI4 silicon tetraiodide
The small prefix is the number of bonds with completed calculations.
Click on an entry for a histogram of the difference distribution.
rms differences (calculated - experiment) in Å
Methods with predefined basis sets
semi-empirical PM6 1 0.037

rms differences (calculated - experiment) in Å
Methods with standard basis sets
STO-3G 3-21G 3-21G*
hartree fock HF 1 0.029 1 0.129 1 0.020
density functional BLYP 1 0.081 1 0.178 1 0.054
B1B95 1 0.034 1 0.004 1 0.004
B3LYP 1 0.059 1 0.144 1 0.029
B3LYPultrafine   1 0.144  
B3PW91 1 0.047 1 0.121 1 0.012
mPW1PW91 1 0.040 1 0.113 1 0.006
M06-2X 1 0.027 1 0.095 1 0.003
PBEPBE 1 0.057 1 0.137 1 0.024
PBEPBEultrafine   1 0.137  
PBE1PBE 1 0.037 1 0.004 1 0.004
HSEh1PBE 1 0.039 1 0.117 1 0.008
TPSSh 1 0.050 1 0.128 1 0.014
wB97X-D 1 0.037 1 0.110 1 0.008
B97D3 1 0.068 1 0.148 1 0.034
STO-3G 3-21G 3-21G*
Moller Plesset perturbation MP2 1 0.048 1 0.152 1 0.012
MP2=FULL 1 0.048 1 0.152 1 0.009
B2PLYP 1 0.051 1 0.143 1 0.020
B2PLYP=FULL 1 0.051 1 0.143 1 0.019
B2PLYP=FULLultrafine 1 0.051 1 0.143 1 0.019
Configuration interaction CID   1 0.148 1 0.014
CISD   1 0.149 1 0.014
STO-3G 3-21G 3-21G*
Quadratic configuration interaction QCISD   1 0.163 1 0.021
Coupled Cluster CCD   1 0.160 1 0.020
STO-3G 3-21G 3-21G*

rms differences (calculated - experiment) in Å
Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD cc-pVTZ-PP aug-cc-pVTZ-PP Def2TZVPP
hartree fock HF 1 0.100   1 0.099   1 0.095 1 0.115 1 0.020   1 0.012
density functional LSDA             1 0.007    
BLYP             1 0.066   1 0.055
B1B95             1 0.001   1 0.008
B3LYP 1 0.132   1 0.131   1 0.119 1 0.135 1 0.037   1 0.027
B3LYPultrafine             1 0.037   1 0.027
B3PW91             1 0.017   1 0.007
mPW1PW91             1 0.010   1 0.001
M06-2X             1 0.001   1 0.007
PBEPBE             1 0.032   1 0.022
PBEPBEultrafine             1 0.032   1 0.022
PBE1PBE             1 0.009   1 0.001
HSEh1PBE             1 0.014   1 0.004
TPSSh             1 0.019   1 0.009
wB97X-D 1 0.099   1 0.098   1 0.087 1 0.097 1 0.012   1 0.003
B97D3             1 0.044   1 0.033
Moller Plesset perturbation MP2 1 0.131   1 0.130   1 0.120 1 0.141 1 0.005   1 0.021
MP2=FULL             1 0.011   1 0.027
MP3             1 0.010    
MP3=FULL             1 0.004    
MP4             1 0.009    
MP4=FULL             1 0.002    
B2PLYP             1 0.019   1 0.008
B2PLYP=FULL             1 0.017   1 0.006
B2PLYP=FULLultrafine             1 0.017   1 0.006
Configuration interaction CID             1 0.000   1 0.012
CISD             1 0.000   1 0.012
Quadratic configuration interaction QCISD             1 0.009   1 0.002
QCISD(T)             1 0.011   1 0.001
QCISD(T)=FULL             1 0.005   1 0.005
Coupled Cluster CCD             1 0.007   1 0.005
CCSD             1 0.008   1 0.003
CCSD=FULL             1 0.002   1 0.009
CCSD(T)             1 0.011   1 0.000
CCSD(T)=FULL             1 0.004   1 0.005
For descriptions of the methods (AM1, HF, MP2, ...) and basis sets (3-21G, 3-21G*, 6-31G, ...) see the glossary in section I.C. Predefined means the basis set used is determined by the method.