return to home page

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

Geometry Comparison

Si(CH3)4 (tetramethylsilane)


distance is atom 1 (Si) to atom 2 (C)

Experimental bond length is 1.875  Å

Display Options
Switch to bar chart display
Calculated bond length in Å
Methods with predefined basis sets
semi-empirical PM6 1.870
composite G2 1.894
G3 1.894
G3B3 1.896
G4 1.888
CBS-Q 1.894

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 aug-cc-pVDZ aug-cc-pVTZ cc-pV(T+d)Z
hartree fock HF 1.864 1.919 1.889 1.918 1.894 1.893 1.892 1.888 1.888 1.887 1.884 1.896 1.896 1.889 1.896 1.889 1.885
density functional LSDA 1.864 1.896 1.873 1.894 1.874 1.873 1.873 1.867 1.867 1.864     1.878 1.866 1.875    
SVWN   1.897     1.872   1.872                    
BLYP 1.895 1.936 1.908 1.935 1.910 1.909 1.910 1.906 1.905 1.901     1.913 1.905      
B1B95             1.885                    
B3LYP 1.880 1.921 1.894 1.920 1.896 1.895 1.895 1.891 1.891 1.888   1.898 1.899 1.891 1.897 1.890 1.886
B3LYPultrafine         1.896                     1.890  
B3PW91 1.876 1.917 1.891 1.916 1.893 1.891 1.891 1.887 1.887 1.885     1.895 1.887      
mPW1PW91 1.872 1.914 1.888 1.913 1.889 1.888 1.888 1.883 1.883 1.881     1.891 1.884      
M06-2X         1.886                        
PBEPBE 1.885 1.926 1.900 1.925 1.901 1.900 1.900 1.895 1.895 1.893     1.904 1.896      
PBE1PBE         1.889                        
HSEh1PBE         1.889                        
TPSSh         1.890   1.889             1.885      
Moller Plesset perturbation MP2 1.880 1.930 1.893 1.933 1.888 1.887 1.886 1.882 1.881 1.880   1.890 1.895 1.883 1.897   1.879
MP2=FULL 1.879 1.930 1.892 1.932 1.885 1.884 1.883 1.879 1.879 1.872     1.892 1.874     1.869
MP3         1.889   1.885                    
MP3=FULL         1.883   1.882                    
MP4   1.937     1.893       1.886                
B2PLYP         1.892                 1.882      
Configuration interaction CID   1.926 1.890 1.928 1.886     1.880                  
CISD   1.926 1.890 1.928 1.886     1.880                  
Quadratic configuration interaction QCISD   1.936 1.897 1.940 1.892 1.891 1.890 1.885 1.885 1.884              
QCISD(T)         1.893                        
Coupled Cluster CCD   1.935 1.896 1.939 1.891 1.890 1.889 1.884 1.884 1.883              
CCSD         1.891                        
CCSD(T)         1.893                        

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 1.917 1.903 1.917 1.901 1.899 1.908
density functional B1B95 1.917 1.901        
B3LYP 1.923 1.906 1.924 1.905 1.902 1.912
Moller Plesset perturbation MP2 1.939 1.901 1.935 1.895 1.916 1.923
Values that are outliers may reflect incorrect atom numbering for different levels of theory.
Please use the error report form to report problems.