Theoretical studies of inorganic compounds. Part XXVIII. Energy decomposition analysis of the chemical bond in main group and transition metal compounds

The nature of the chemical bond in the main group diborane(4) compounds X2B-BX2 (X = H, F, Cl, Br, I) and in the Fischer- and Schrock-type transition metal carbene and carbyne complexes and heavier homologues (CO)(5)W-CH2, (CO)(5)W-E(OH)(2), Cl4W-EH2, Cl(CO)(4)W-EH and Cl3W-EH (E = C, Si, Ge, Sn, Pb) have been investigated with an energy decomposition analysis (EDA). The results give a deep insight into the nature of the chemical interactions. The EDA results can be used as a bridge between the heuristic models of experimental chemists which have been proven as useful ordering schemes for experimental observations and the physical mechanism which leads to a chemical bond. At the time the data give a well defined qantitative answer to the questions about the strength of the covalent and electrostatic interactions and about the contributions of sigma and pi electrons to the covalent bond.