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Comparison of experiment and theory for rHI

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

rms differences (calculated - experiment) in Å
Methods with standard basis sets
3-21G 3-21G* 6-31G* 6-311G* 6-311G** Def2TZVPP
hartree fock HF 1 0.029 1 0.022   1 0.015 1 0.000 1 0.028
density functional BLYP 1 0.068 1 0.051   1 0.045 1 0.030  
B1B95   1 0.030   1 0.023 1 0.009  
B3LYP 1 0.052 1 0.038   1 0.032 1 0.017 1 0.001
B3PW91 1 0.048 1 0.033   1 0.028 1 0.014  
mPW1PW91 1 0.045 1 0.031   1 0.025 1 0.011  
M06-2X   1 0.028        
PBEPBE 1 0.062 1 0.045   1 0.040 1 0.025 1 0.010
wB97X-D   1 0.028        
B97D3 1 0.061          
3-21G 3-21G* 6-31G* 6-311G* 6-311G** Def2TZVPP
Moller Plesset perturbation MP2 1 0.048 1 0.036 1 0.033 2 0.033 1 0.003 1 0.035
MP2=FULL 1 0.048 1 0.036   1 0.029 1 0.002  
Configuration interaction CID 1 0.061 1 0.042   1 0.031 1 0.003  
CISD 1 0.063 1 0.043   1 0.032 1 0.002  
3-21G 3-21G* 6-31G* 6-311G* 6-311G** Def2TZVPP
Quadratic configuration interaction QCISD 1 0.065 1 0.047   1 0.039 1 0.003  
QCISD(T) 1 0.065 1 0.049   1 0.042 1 0.004  
Coupled Cluster CCD 1 0.063 1 0.046   1 0.038 1 0.002  
CCSD(T) 1 0.065 1 0.049   1 0.042 1 0.004  
3-21G 3-21G* 6-31G* 6-311G* 6-311G** Def2TZVPP

rms differences (calculated - experiment) in Å
Methods with effective core potentials (select basis sets)
daug-cc-pVDZ daug-cc-pVTZ daug-cc-pVQZ Sadlej_pVTZ CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
hartree fock HF         1 0.007   1 0.004   1 0.006 1 0.008
density functional B1B95         1 0.032   1 0.030   1 0.029 1 0.032
B3LYP         1 0.031   1 0.029   1 0.027 1 0.030
Moller Plesset perturbation MP2         1 0.028   1 0.025   1 0.024 1 0.028
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.