Intrinsic reactivity index as a single scale directed toward both electrophilicity and nucleophilicity using frontier molecular orbitals

A theoretical intrinsic reactivity index (IRI) is introduced through analysis of the ω, ɛ correlation (Tetrahedron Lett. 2013, 54, 339-342). The index is valid as a single scale directed toward both electrophilicity and nucleophilicity using the energy levels of frontier molecular orbitals. Linear correlations of IRI values with various chemical properties are available for a wide range of reactivity. A striking example of a fair linear correlation of IRI values of benzhydryl cations with Mayr's electrophilicity parameter E is described.