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IV.D.1. (XII.C.1.)

Geometry Comparison

HO2- (Hydroperoxy anion)


distance is atom 1 (O) to atom 3 (H)
No experimental bond length available. Calculated bond lengths are shown.
Calculated bond length in Å
Methods with predefined basis sets
semi-empirical AM1 0.995
PM3 0.942
PM6 0.987
composite G2 0.946
G3 0.946
G3B3 0.971
CBS-Q 0.942
Calculated bond length in Å
Methods with standard basis sets
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ
hartree fock HF 1.021 0.976 0.976 0.955 0.946 0.943 0.941 0.938 0.938 0.939 0.940 0.944 0.937 0.936 0.941 0.938 0.937
ROHF 1.021 0.976 0.976 0.955 0.946 0.943 0.941 0.938 0.938 0.939   0.944 0.937 0.936 0.941 0.938 0.937
density functional LSDA 1.287 1.031 1.031 0.992 0.981 0.977 0.975 0.971 0.967 0.973   0.974 0.969 0.969 0.976 0.973 0.971
SVWN   1.031     0.981   0.975                    
BLYP 1.378 1.021 1.021 0.996 0.982 0.978 0.977 0.973 0.969 0.974   0.978 0.970        
B1B95 1.101 1.000 1.000 0.978 0.966 0.962 0.961 0.958 0.956 0.958   0.963 0.956 0.955 0.961 0.957 0.956
B3LYP 1.134 1.008 1.008 0.984 0.971 0.968 0.966 0.963 0.960 0.963 0.963 0.968 0.960 0.959 0.965 0.962 0.961
B3LYPultrafine         0.971                        
B3PW91 1.129 1.003 1.003 0.981 0.969 0.965 0.964 0.961 0.959 0.961   0.966 0.959        
mPW1PW91 1.101 1.000 1.000 0.978 0.966 0.963 0.961 0.959 0.956 0.959   0.964 0.956        
M06-2X         0.967                        
PBEPBE 1.352 1.017 1.017 0.993 0.980 0.976 0.975 0.971 0.968 0.972   0.976 0.969 0.969     0.971
HSEh1PBE         0.967                        
Moller Plesset perturbation MP2FC 1.053 1.002 1.002 0.984 0.970 0.964 0.966 0.958 0.956 0.958 0.961 0.964 0.958   0.968 0.963  
MP2FU 1.053 1.002 1.002 0.984 0.970 0.963 0.965 0.957 0.955 0.958   0.964 0.957     0.960  
ROMP2 1.053 1.001 1.001 0.984 0.970 0.964 0.966 0.958 0.956 0.958   0.964 0.958 0.957 0.968 0.963 0.960
MP3         0.967                        
MP4   1.008     0.973       0.957       0.959        
B2PLYP         0.969   0.965                    
Configuration interaction CID   0.998 0.998 0.977 0.963     0.951                  
CISD   0.999 0.999 0.978 0.964     0.951                  
Quadratic configuration interaction QCISD   1.007 1.007 0.985 0.971 0.963 0.964 0.958 0.955 0.957   0.964 0.956        
QCISD(T)         0.973             0.966 0.958   0.968 0.963  
Coupled Cluster CCD   1.005 1.005 0.983 0.970 0.962 0.962 0.957 0.954 0.956   0.963 0.954   0.963 0.957  
CCSD         0.971                        
CCSD(T)         0.973             0.966 0.958   0.968 0.962  
CCSD(T)=FULL         0.973                        
Calculated bond length in Å
Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
hartree fock HF 0.960 0.950 0.956 0.947 0.957 0.957
density functional B3LYP 0.992 0.976 0.986 0.971 0.987 0.987
Moller Plesset perturbation MP2FC 0.993 0.977 0.987 0.972 0.990 0.990
Values that are outliers may reflect different atom numbering for different levels of theory.
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