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Comparison of experiment and theory for rCI

Species with coordinate rCI
Species Name
CH3I methyl iodide
CF3I trifluoroiodomethane
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

rms differences (calculated - experiment) in Å
Methods with standard basis sets
3-21G 3-21G* 6-31G* 6-311G* 6-311G**
hartree fock HF 1 0.058 1 0.043   2 0.017  
density functional LSDA       1 0.014  
SVWN       1 0.014  
BLYP 1 0.105 1 0.084   2 0.074  
B1B95 1 0.049 1 0.032   2 0.013  
B3LYP 1 0.077 1 0.058   2 0.041  
B3PW91 1 0.058 1 0.040   2 0.025  
mPW1PW91 1 0.051 1 0.034   2 0.018  
M06-2X       1 0.013  
PBEPBE 1 0.072 1 0.053   2 0.045  
PBE1PBE       1 0.020  
wB97X-D   2 0.039      
B97D3 2 0.109        
3-21G 3-21G* 6-31G* 6-311G* 6-311G**
Moller Plesset perturbation MP2 1 0.068 1 0.063 2 0.037 3 0.017  
MP2=FULL 1 0.067 1 0.062   2 0.019  
ROMP2       1 0.020  
Configuration interaction CID 1 0.070 1 0.059   2 0.010  
CISD 1 0.074 1 0.061   2 0.012  
3-21G 3-21G* 6-31G* 6-311G* 6-311G**
Quadratic configuration interaction QCISD 1 0.083 1 0.071   2 0.025 1 0.022
QCISD(T) 1 0.086 1 0.077   1 0.033  
Coupled Cluster CCD 1 0.076 1 0.068   2 0.021  
CCSD(T) 1 0.086 1 0.077   1 0.032 1 0.026
3-21G 3-21G* 6-31G* 6-311G* 6-311G**

rms differences (calculated - experiment) in Å
Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
hartree fock HF 2 0.032   2 0.028   2 0.032 2 0.036
density functional B1B95 1 0.041   1 0.036   1 0.041 1 0.047
B3LYP 2 0.051   2 0.064   2 0.045 2 0.054
Moller Plesset perturbation MP2 2 0.046   2 0.042   2 0.045 2 0.051
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.