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)₅W–CH₂, (CO)₅W–E(OH)₂, Cl₄W–EH₂, Cl(CO)₄W–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 σ and π electrons to the covalent bond.