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Comparison of experiment and theory for rHI

18 10 23 14 56
Species with coordinate rHI
Species Name
HI Hydrogen iodide
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 PM3 1 0.068

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 0.029 1 0.022   2 0.012 1 0.000
ROHF       1 0.008  
density functional LSDA       1 0.037  
BLYP 1 0.068 1 0.051   2 0.044 1 0.030
B1B95 1 0.044 1 0.030   2 0.022 1 0.009
B3LYP 1 0.052 1 0.038   2 0.031 1 0.017
B3LYPultrafine       1 0.030  
B3PW91 1 0.048 1 0.033   2 0.027 1 0.014
mPW1PW91 1 0.045 1 0.031   2 0.024 1 0.011
M06-2X   1 0.028   1 0.018  
PBEPBE 1 0.062 1 0.045   2 0.040 1 0.025
PBEPBEultrafine       1 0.040  
PBE1PBE       1 0.025  
HSEh1PBE       1 0.026  
TPSSh       1 0.025  
wB97X-D   1 0.028   1 0.021  
B97D3 1 0.057     1 0.033  
3-21G 3-21G* 6-31G* 6-311G* 6-311G**
Moller Plesset perturbation MP2 1 0.048 1 0.036 1 0.033 2 0.032 1 0.003
MP2=FULL 1 0.048 1 0.036   2 0.028 1 0.002
ROMP2       1 0.024  
MP3       1 0.031  
MP3=FULL       1 0.033  
MP4       1 0.036  
MP4=FULL       1 0.037  
B2PLYP       1 0.026  
B2PLYP=FULL       1 0.026  
B2PLYP=FULLultrafine       1 0.026  
Configuration interaction CID 1 0.061 1 0.042   2 0.030 1 0.003
CISD 1 0.063 1 0.043   2 0.030 1 0.002
3-21G 3-21G* 6-31G* 6-311G* 6-311G**
Quadratic configuration interaction QCISD 1 0.065 1 0.047   2 0.038 1 0.003
QCISD(T) 1 0.065 1 0.049   2 0.041 1 0.004
QCISD(T)=FULL       1 0.041  
Coupled Cluster CCD 1 0.063 1 0.046   2 0.037 1 0.002
CCSD       1 0.037  
CCSD=FULL       1 0.038  
CCSD(T) 1 0.065 1 0.049   2 0.041 1 0.004
CCSD(T)=FULL       1 0.042  
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 1 0.007   1 0.004   1 0.006 1 0.008 2 0.008   2 0.014
ROHF             2 0.009   2 0.014
density functional LSDA             2 0.019   2 0.013
BLYP             2 0.026   2 0.020
B1B95 1 0.032   1 0.030   1 0.029 1 0.032 2 0.004   2 0.002
B3LYP 1 0.031   1 0.029   1 0.027 1 0.030 2 0.012   2 0.007
B3LYPultrafine             2 0.012   2 0.007
B3PW91             2 0.009   2 0.003
mPW1PW91             2 0.006   2 0.000
M06-2X             2 0.003   2 0.003
PBEPBE             2 0.022   2 0.016
PBEPBEultrafine             2 0.022   2 0.016
PBE1PBE             2 0.007   2 0.002
HSEh1PBE             2 0.009   2 0.003
TPSSh             2 0.010   2 0.004
wB97X-D             2 0.005   2 0.001
B97D3             2 0.017   2 0.011
Moller Plesset perturbation MP2 1 0.028   1 0.025   1 0.024 1 0.028 2 0.009   2 0.019
MP2=FULL             2 0.011   2 0.023
ROMP2             2 0.009   2 0.019
MP3             2 0.005   2 0.014
MP3=FULL             2 0.008   2 0.018
MP4             2 0.002   2 0.010
MP4=FULL             2 0.004   2 0.015
B2PLYP             2 0.004   2 0.003
B2PLYP=FULL             2 0.003   2 0.005
B2PLYP=FULLultrafine             2 0.003   2 0.005
Configuration interaction CID             2 0.007   2 0.021
CISD             2 0.006   2 0.020
Quadratic configuration interaction QCISD             2 0.002   2 0.011
QCISD(T)             2 0.001   2 0.008
QCISD(T)=FULL             2 0.002   2 0.013
Coupled Cluster CCD             2 0.003   2 0.012
CCSD             2 0.002   2 0.011
CCSD=FULL             2 0.004   2 0.016
CCSD(T)             2 0.001   2 0.008
CCSD(T)=FULL             2 0.002   2 0.013
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.