title: Ring currents in benzo- and benzocyclobutadieno-annelated biphenylene derivatives.
abstract: The effect of benzo and benzocyclobutadieno annelation on the current density induced in a series of biphenylene derivatives is examined at the B3LYP/cc-pVDZ level of theory, by using the CTOCD-DZ method. Angular benzo annelation increases, whereas linear benzo annelation decreases the intensity of paratropic (antiaromatic) current density along the four-membered ring of biphenylene. The opposite effect is found for benzocyclobutadieno annelation. It is shown that the extent of local aromaticity of the four-membered ring in biphenylene congeners can vary from highly antiaromatic to nonaromatic, as a result of different modes of annelation.
authors.affiliation: Faculty of Science, University of Kragujevac, Radoja Domanovića 12, 34000 Kragujevac (Serbia). slavkoradenkovic@kg.ac.rs.
authors.forename: Slavko
authors.initials: S
authors.lastname: Radenković
authors.forename: Jelena
authors.initials: J
authors.lastname: Tošović
authors.forename: Remco W A
authors.initials: RW
authors.lastname: Havenith
authors.forename: Patrick
authors.initials: P
authors.lastname: Bultinck
keywords: aromaticity; density functional calculations; hydrocarbons; magnetic properties; polycycles