Perspectives on the Role of Frontier Molecular Orbitals in the Study of Chemical Reactivity: An Updated Review

Abstract

Molecular orbitals are critical in the rationalization of several chemical reactions. Thus, the Frontier molecular orbital theory, proposed by Fukui's group, postulated the importance of the highest occupied molecular orbital (HOMO) and the unoccupied molecular orbital of lowest energy (LUMO) for chemical reactions. It should be kept in mind, however, that there are limitations of this theory and new perspectives about the chemical reactivity have recently been arisen based on composition and location of other frontier molecular orbitals. In this review, we have reported the development of the Frontier Effective-for-Reaction Molecular (FERMO) concept, which describes the breaking and formation of new chemical bonds and can be in turn provide important clues that modulate chemical reactivity of atoms and molecules.