title: Reversible electron-transfer reactions within a nanoscale metal oxide cage mediated by metallic substrates.
abstract: Transition metal oxides exhibit a rich collection of electronic properties and have many practical applications in areas such as catalysis and ultra-high-density magnetic data storage. Therefore the development of switchable molecular transition metal oxides has potential for the engineering of single-molecule devices and nanoscale electronics. At present, the electronic properties of transition metal oxides can only be tailored through the irreversible introduction of dopant ions, modifying the electronic structure by either injecting electrons or core holes. Here we show that a molybdenum(VI) oxide 'polyoxometalate' molecular nanocluster containing two embedded redox agents is activated by a metallic surface and can reversibly interconvert between two electronic states. Upon thermal activation two electrons are ejected from the active sulphite anions and delocalized over the metal oxide cluster cage, switching it from a fully oxidized state to a two-electron reduced state along with the concomitant formation of an S-S bonding interaction between the two sulphur centres inside the cluster shell.
authors.affiliation: Department of Chemistry, The University of Glasgow, Glasgow G12 8QQ, UK.
authors.forename: Christopher
authors.initials: C
authors.lastname: Fleming
authors.forename: De-Liang
authors.initials: DL
authors.lastname: Long
authors.forename: Nicola
authors.initials: N
authors.lastname: McMillan
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Johnston
authors.forename: Nicolas
authors.initials: N
authors.lastname: Bovet
authors.forename: Vin
authors.initials: V
authors.lastname: Dhanak
authors.forename: Nikolaj
authors.initials: N
authors.lastname: Gadegaard
authors.forename: Paul
authors.initials: P
authors.lastname: Kögerler
authors.forename: Leroy
authors.initials: L
authors.lastname: Cronin
authors.forename: Malcolm
authors.initials: M
authors.lastname: Kadodwala
mesh_terms: D003198:Computer Simulation; D004579:Electron Transport; D004583:Electrons; D046911:Macromolecular Substances; D008422:Materials Testing; D008956:Models, Chemical; D008982:Molybdenum / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000379:methods*; D010087:Oxides / Q000737:chemistry; D017973:Tungsten Compounds / Q000737:chemistry*; D000099294:Polyoxometalates
chemical_list: D046911:Macromolecular Substances; D008982:Molybdenum; D010087:Oxides; D017973:Tungsten Compounds; C102296:polyoxometalate I; D000099294:Polyoxometalates