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Comparison of experiment and theory for rIO

18 10 23 14 56
Species with coordinate rIO
Species Name
IO Iodine monoxide
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 1 0.063
PM3 1 0.001
PM6 1 0.099

rms differences (calculated - experiment) in Å
Methods with standard basis sets
STO-3G 3-21G
hartree fock HF 1 0.339 1 1.435
ROHF   1 0.145
density functional BLYP 1 0.200 1 0.180
B1B95 1 0.169 1 0.080
B3LYP 1 0.180 1 0.159
B3LYPultrafine   1 0.159
B3PW91 1 0.178 1 0.148
mPW1PW91 1 0.174 1 0.145
M06-2X 1 0.159 1 0.146
PBEPBE 1 0.191 1 0.161
PBEPBEultrafine   1 0.161
PBE1PBE 1 0.173 1 0.084
HSEh1PBE 1 0.175 1 0.147
TPSSh 1 0.185 1 0.156
wB97X-D 1 0.173 1 0.141
B97D3 1 0.199 1 0.164
STO-3G 3-21G
Moller Plesset perturbation MP2 1 0.138 1 0.104
MP2=FULL 1 0.138 1 0.103
ROMP2 1 0.178 1 0.141
MP3=FULL   1 0.111
MP4   1 0.117
MP4=FULL   1 0.116
B2PLYP 1 0.176 1 0.157
B2PLYP=FULL 1 0.176 1 0.157
B2PLYP=FULLultrafine 1 0.176 1 0.157
Configuration interaction CID   1 0.118
CISD   1 0.161
STO-3G 3-21G
Quadratic configuration interaction QCISD   1 0.194
Coupled Cluster CCD   1 0.116
STO-3G 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 6.402   1 6.605   1 6.399 1 6.408 1 0.066   1 0.050
ROHF             1 0.061   1 0.048
density functional LSDA             1 0.004    
BLYP             1 0.058   1 0.042
B1B95             1 0.012   1 0.004
B3LYP 1 0.153   1 0.152   1 0.143 1 0.158 1 0.034   1 0.018
B3LYPultrafine             1 0.034   1 0.018
B3PW91             1 0.021   1 0.005
mPW1PW91             1 0.018   1 0.001
M06-2X             1 0.019   1 0.002
PBEPBE             1 0.036   1 0.020
PBEPBEultrafine             1 0.036   1 0.020
PBE1PBE             1 0.016   1 0.001
HSEh1PBE             1 0.020   1 0.003
TPSSh             1 0.030   1 0.014
wB97X-D 1 0.141   1 0.140   1 0.131 1 0.148 1 0.011   1 0.006
B97D3             1 0.039   1 0.023
Moller Plesset perturbation MP2 1 0.085   1 0.085   1 0.084 1 0.091 1 0.020   1 0.004
MP2=FULL             1 0.018   1 0.000
ROMP2             1 0.038   1 0.019
MP3             1 0.040   1 0.026
MP3=FULL             1 0.038   1 0.022
MP4             1 0.030   1 0.013
MP4=FULL             1 0.027   1 0.009
B2PLYP             1 0.017   1 0.001
B2PLYP=FULL             1 0.016   1 0.002
B2PLYP=FULLultrafine             1 0.016   1 0.002
Configuration interaction CID             1 0.038   1 0.019
CISD             1 0.034   1 0.017
Quadratic configuration interaction QCISD             1 0.032   1 0.015
QCISD(T)             1 0.035   1 0.018
QCISD(T)=FULL             1 0.032   1 0.013
Coupled Cluster CCD             1 0.039   1 0.024
CCSD             1 0.028   1 0.010
CCSD=FULL             1 0.025   1 0.006
CCSD(T)             1 0.032   1 0.014
CCSD(T)=FULL             1 0.029   1 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.