return to home page

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

Geometry Comparison

MgOH (magnesium hydroxide)


distance is atom 1 (O) to atom 2 (Mg)

Experimental bond length is 1.767  Å

Display Options
Switch to bar chart display
Calculated bond length in Å
Methods with predefined basis sets
semi-empirical PM3 1.773
PM6 1.726
composite G2 1.769
G3 1.769
G3B3 1.820
G4 1.769
CBS-Q 1.765

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) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ
hartree fock HF 1.778 1.727 1.725 1.757 1.809 1.762   1.766 1.768 1.758 1.759 1.775 1.766 1.760 1.758   1.762 1.760
ROHF   1.727 1.725   1.768 1.762 1.782 1.766                    
density functional LSDA 1.799 1.732 1.724 1.755 1.806 1.803 1.809 1.796 1.800 1.780     1.799 1.789   1.795    
SVWN   1.732     1.806   1.783                      
BLYP 1.833 1.758 1.751 1.781 1.845 1.841 1.854 1.840 1.845 1.823           1.839    
B1B95 1.808 1.739 1.732 1.764 1.805 1.803 1.809 1.791 1.791 1.784     1.793 1.787   dnf    
B3LYP 1.815 1.742 1.734 1.766 1.820 1.814 1.823 1.808   1.786 1.774 1.806 1.807   1.791   1.798 1.776
B3LYPultrafine         1.820                       1.779  
B3PW91     1.735 1.767 1.814 1.809 1.816 1.800               1.807    
mPW1PW91   1.739   1.763 1.810 1.804 1.811 1.794 1.796 1.786           1.803    
M06-2X         1.816                          
PBEPBE   1.755     1.840 1.837 1.847 1.835 1.841 1.821 1.818   1.836 1.828        
PBEPBEultrafine         1.840                          
PBE1PBE         1.811                          
HSEh1PBE         1.811                          
TPSSh         1.777   1.792             1.775        
Moller Plesset perturbation MP2   1.741 1.736 1.773 1.809 1.801 1.845 1.788 1.798 1.780   1.796 1.782       1.789  
MP2=FULL   1.741     1.805 1.779 1.804 1.782               1.807    
MP3         1.796   1.774                      
MP3=FULL         1.775   1.794                      
MP4         1.814     1.795           1.805        
B2PLYP         1.814                 1.775        
B2PLYP=FULLultrafine         1.819                          
Configuration interaction CID         1.794     1.771                    
CISD         1.799 1.774                        
Quadratic configuration interaction QCISD   1.743     1.809   1.805 1.786         1.778 1.791        
QCISD(T)         1.814     1.793                    
Coupled Cluster CCD         1.799     1.775         1.775          
CCSD         1.806     1.781                    
CCSD(T)         1.813 1.804   1.791           1.799        

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 1.809 1.784 1.763 1.768 1.761 1.767
density functional B1B95 1.807 1.804        
B3LYP 1.811 1.822 1.777 1.807 1.764 1.772
Moller Plesset perturbation MP2 1.822 1.799 1.781 1.782 1.773 1.784
Values that are outliers may reflect incorrect atom numbering for different levels of theory.
Please use the error report form to report problems.