Molecular switches from benzene derivatives adsorbed on metal surfaces

Abstract

© 2013 Macmillan Publishers Limited ; Transient precursor states are often experimentally observed for molecules adsorbing on surfaces. However, such precursor states are typically rather short-lived, quickly yielding to more stable adsorption configurations. Here we employ first-principles calculations to systematically explore the interaction mechanism for benzene derivatives on metal surfaces, enabling us to selectively tune the stability and the barrier between two metastable adsorption states. In particular, in the case of the tetrachloropyrazine molecule, two equally stable adsorption states are identified with a moderate and conceivably reversible barrier between them. We address the feasibility of experimentally detecting the predicted bistable behaviour and discuss its potential usefulness in a molecular switch. ; W.L. and S.N.F. are grateful to the Alexander von Humboldt Foundation. J.C. is a Ramón y Cajal fellow and Newton Alumnus supported by the Spanish Government and The Royal Society. J.C. is grateful for support from the Marie Curie Career Integration Grant (FP7-PEOPLE-2011-CIG NanoWGS). A.T. acknowledges support from the European Research Council (ERC Starting Grant VDW-CMAT). ; Peer Reviewed