title: Electrically switchable magnetic molecules: inducing a magnetic coupling by means of an external electric field in a mixed-valence polyoxovanadate cluster.
abstract: Herein we evaluate the influence of an electric field on the coupling of two delocalized electrons in the mixed-valence polyoxometalate (POM) [GeV14 O40 ](8-) (in short V14 ) by using both a t-J model Hamiltonian and DFT calculations. In absence of an electric field the compound is paramagnetic, because the two electrons are localized on different parts of the POM. When an electric field is applied, an abrupt change of the magnetic coupling between the two delocalized electrons can be induced. Indeed, the field forces the two electrons to localize on nearest-neighbors metal centers, leading to a very strong antiferromagnetic coupling. Both theoretical approaches have led to similar results, emphasizing that the sharp spin transition induced by the electric field in the V14 system is a robust phenomenon, intramolecular in nature, and barely influenced by small changes on the external structure.
authors.affiliation: Instituto de Ciencia Molecular (ICMol), Universidad de Valencia, C/Catedrático José Beltrán N° 2, 46980 Paterna (Spain).
authors.forename: Salvador
authors.initials: S
authors.lastname: Cardona-Serra
authors.forename: Juan M
authors.initials: JM
authors.lastname: Clemente-Juan
authors.forename: Eugenio
authors.initials: E
authors.lastname: Coronado
authors.forename: Alejandro
authors.initials: A
authors.lastname: Gaita-Ariño
authors.forename: Nicolas
authors.initials: N
authors.lastname: Suaud
authors.forename: Ondrej
authors.initials: O
authors.lastname: Svoboda
authors.forename: Roland
authors.initials: R
authors.lastname: Bastardis
authors.forename: Nathalie
authors.initials: N
authors.lastname: Guihéry
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Palacios
keywords: mixed valence; molecular magnetism; polyoxometalate; spintronics; switchable materials