title: Electronic nature of carbonium ions and their silicon analogues.
abstract: Nonclassical ions or carbonium ions have multi-center bonding from delocalized sigma or pi electrons. The 2-norbornyl cation, its derivative 6,6-difluoro-2-norbornyl cation, tris-homocyclopropenyl cation, 7-norbornenyl cation, and 4-cyclopentenyl cation and their corresponding silicon analogues were studied in this work. All carbocations have topologically different 3c-2e systems. The magnitude of all delocalization indexes between each atomic pair of the 3c-2e bond can be used to predict homoaromaticity. The silicon analogues have a topologically different 3c-2e bond from their corresponding carbocation.
authors.affiliation: Universidade Federal do Rio de Janeiro, Instituto de Química, Avenida Athos da Silveira Ramos, 149, CT Bloco A, Sala 622, Cidade UniversitAria, Ilha do Fundão, Rio de Janeiro, BR 21941-909, Brazil. cfirme@iq.ufrj.br
authors.forename: Caio L
authors.initials: CL
authors.lastname: Firme
authors.forename: O A C
authors.initials: OA
authors.lastname: Antunes
authors.forename: Pierre M
authors.initials: PM
authors.lastname: Esteves