return to home page

IV.D.8.

Average Bond Length Differences by Model Chemistry

The following tables the average bond length differences (theory - experiment) for various model chemistries. Only averages with more than 100 bond lengths are displayed.
Bond lengths in Å.
Click on an entry for the list of molecules and bonds.
Methods with predefined basis sets

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) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z
hartree fock HF 0.014 0.033 0.001 0.042 0.009 -0.007 0.003 -0.007 -0.007 -0.012 -0.013 0.002 -0.002 -0.013 -0.011 -0.003 -0.004 -0.011 -0.015
density functional LSDA 0.024 0.028 0.009 0.034   0.004 0.012 0.002 0.001 -0.003     0.011 -0.001   0.010      
SVWN             0.006                        
BLYP 0.047 0.054 0.032 0.053   0.023 0.036 0.023 0.021 0.015     0.029 0.018   0.040      
B1B95 0.024 0.027 0.008 0.032   0.001 0.009 0.001 0.000 -0.005     0.007 -0.005   0.005      
B3LYP 0.039 0.038 0.015 0.039   0.008 0.019 0.007 0.012 0.001 0.012 0.016 0.014 0.009 0.004 0.015 0.005 0.003 0.005
B3PW91 0.032 0.035 0.012 0.035   0.004 0.016 0.004 0.007 -0.002     0.011 0.001   0.021      
mPW1PW91 0.016 0.032 0.014 0.032   0.002 0.012 0.001 0.001 -0.004     0.007 -0.002   0.019      
M06-2X         0.009                            
PBEPBE 0.049 0.050 0.037 0.066   0.016 0.028 0.016 0.015 0.009 0.021   0.023 0.012     0.025    
Moller Plesset perturbation MP2 0.040 0.045 0.018 0.048   0.004 0.016 0.005 0.004 -0.002   0.015 0.014 -0.000 0.001 0.019 0.005 0.002 -0.001
MP2=FULL 0.043 0.048 0.024 0.058   0.002 0.016 0.003 0.006 -0.011     0.013 -0.005 -0.010 0.026     -0.005
MP4   0.071                       0.013          
B2PLYP         0.014                            
Configuration interaction CID   0.053 0.020 0.066       0.002                      
CISD   0.054 0.026 0.072       0.006                      
Quadratic configuration interaction QCISD   0.061 0.032 0.066   0.011 0.021 0.010 0.008 0.001     0.020 0.008          
QCISD(T)               0.018                      
Coupled Cluster CCD   0.056 0.025 0.061   0.006 0.016 0.007 0.006 -0.007     0.015 -0.001          
CCSD(T)           0.030   0.018         0.030 0.013          

Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
hartree fock HF 0.068 0.004 0.073 -0.003 0.060 0.062
density functional B1B95 0.044 0.016        
B3LYP 0.056 0.024 0.050 0.016 0.045 0.042
Moller Plesset perturbation MP2 0.067 0.023 0.059 0.014 0.056 0.055
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.