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Comparison of experiment and theory for rCI

18 10 23 14 56
Species with coordinate rCI
Species Name
CH3I methyl iodide
C2H5I Ethyl iodide
CH2I2 Diiodomethane
CH2FI fluoroiodomethane
ICN Cyanogen iodide
CI4 tetraiodomethane
CH2ClI chloroiodomethane
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
semi-empirical AM1 6 0.082
PM3 7 0.134
PM6 6 0.021

rms differences (calculated - experiment) in Å
Methods with standard basis sets
STO-3G 3-21G 3-21G* 6-31G* 6-311G* 6-311G**
hartree fock HF 6 0.018 7 0.051 6 0.037   6 0.021 3 0.020
ROHF   1 0.040 1 0.036      
density functional LSDA 1 0.012 1 0.006 1 0.006   5 0.012 2 0.014
BLYP 6 0.062 7 0.106 6 0.083   6 0.073 3 0.075
B1B95 6 0.025 7 0.032 6 0.028   6 0.013 3 0.014
B3LYP 6 0.038 7 0.076 6 0.055   6 0.042 3 0.043
B3LYPultrafine   6 0.076     4 0.043 2 0.045
B3PW91 6 0.032 7 0.059 6 0.039   6 0.025 3 0.026
mPW1PW91 6 0.027 7 0.052 6 0.033   6 0.019 3 0.019
M06-2X 6 0.020 6 0.047 7 0.027   5 0.015 2 0.016
PBEPBE 6 0.047 7 0.077 6 0.054   6 0.043 3 0.044
PBEPBEultrafine   6 0.078     4 0.043 2 0.048
PBE1PBE 6 0.026 6 0.031 5 0.031   5 0.018 2 0.019
HSEh1PBE 6 0.027 6 0.054 5 0.034   4 0.021 2 0.023
TPSSh 6 0.039 6 0.068 5 0.046   4 0.035 2 0.038
wB97X-D 6 0.025 6 0.048 7 0.033   4 0.018 2 0.019
B97D3 6 0.059 8 0.095 5 0.067   4 0.055 2 0.062
STO-3G 3-21G 3-21G* 6-31G* 6-311G* 6-311G**
Moller Plesset perturbation MP2 6 0.033 7 0.071 6 0.060 2 0.037 6 0.017 3 0.015
MP2=FULL 6 0.033 7 0.069 6 0.059   6 0.018 3 0.015
ROMP2 1 0.032   1 0.053   1 0.020  
MP3         4 0.022 2 0.020
MP3=FULL   5 0.071 4 0.058   4 0.022 2 0.020
MP4   5 0.088     4 0.031 2 0.031
MP4=FULL   5 0.086     3 0.032 2 0.032
B2PLYP 6 0.032 6 0.071 5 0.054   4 0.032 2 0.033
B2PLYP=FULL 6 0.032 6 0.071 5 0.054   4 0.033 2 0.034
B2PLYP=FULLultrafine 6 0.032 6 0.071 5 0.054   4 0.033 2 0.034
Configuration interaction CID   7 0.064 6 0.051   6 0.012 3 0.008
CISD   7 0.067 6 0.053   6 0.013 3 0.010
STO-3G 3-21G 3-21G* 6-31G* 6-311G* 6-311G**
Quadratic configuration interaction QCISD   7 0.079 6 0.067   6 0.027 3 0.023
QCISD(T)   1 0.086 1 0.077   5 0.034 3 0.030
QCISD(T)=FULL         4 0.033 2 0.033
Coupled Cluster CCD   7 0.073 6 0.063   6 0.022 3 0.018
CCSD         4 0.026 2 0.023
CCSD=FULL         4 0.026 2 0.023
CCSD(T)   1 0.086 1 0.077   5 0.032 3 0.029
CCSD(T)=FULL         4 0.033 2 0.031
STO-3G 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 cc-pVTZ-PP aug-cc-pVTZ-PP Def2TZVPP
hartree fock HF 8 0.034   8 0.032   8 0.034 8 0.039 7 0.009   8 0.006
ROHF             1 0.009   3 0.005
density functional LSDA             7 0.012   2 0.024
BLYP             7 0.059   7 0.051
B1B95 1 0.041   1 0.036   1 0.041 1 0.047 7 0.005   7 0.009
B3LYP 8 0.059   8 0.060   8 0.051 8 0.059 7 0.030   8 0.026
B3LYPultrafine             7 0.030   7 0.022
B3PW91             7 0.012   7 0.007
mPW1PW91             7 0.007   7 0.006
M06-2X             7 0.004   7 0.006
PBEPBE             7 0.029   8 0.027
PBEPBEultrafine             7 0.029   7 0.021
PBE1PBE             7 0.006   7 0.007
HSEh1PBE             7 0.008   7 0.006
TPSSh             7 0.021   7 0.014
wB97X-D 6 0.037   6 0.035   6 0.031 6 0.035 7 0.005   7 0.004
B97D3             7 0.044   7 0.036
Moller Plesset perturbation MP2 8 0.057   8 0.055   8 0.054 8 0.060 7 0.009   8 0.019
MP2=FULL             7 0.013   7 0.027
ROMP2             1 0.011   3 0.021
MP3             7 0.004   6 0.010
MP3=FULL             7 0.007   6 0.016
MP4             7 0.007   6 0.005
MP4=FULL             7 0.005   6 0.011
B2PLYP             7 0.015   7 0.008
B2PLYP=FULL             7 0.014   7 0.006
B2PLYP=FULLultrafine             7 0.014   7 0.006
Configuration interaction CID             7 0.013   7 0.024
CISD             7 0.012   7 0.023
Quadratic configuration interaction QCISD             7 0.004   7 0.009
QCISD(T)             7 0.007   7 0.003
QCISD(T)=FULL             7 0.004   7 0.009
QCISD(TQ)                 1 0.001
Coupled Cluster CCD             7 0.005   7 0.012
CCSD             7 0.004   7 0.010
CCSD=FULL             7 0.006   7 0.016
CCSD(T)             7 0.006   7 0.003
CCSD(T)=FULL             7 0.003   7 0.010
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.