title: A switch based on self-assembled thymine.
abstract: The DNA base thymine is deposited at 100 K on Cu(111) and investigated and manipulated by low-temperature scanning tunneling microscopy at 5 K. At submonolayer coverage paired rows are observed. At monolayer coverage a hexagonal commensurate self-assembled layer with the methyl group pointing away from the surface forms. A reversible local manipulation of molecules within the self-assembled layer is demonstrated. This manipulation is interpreted as an out-of-plane relaxation of molecules within the layer induced by the change of the adsorption geometry of individual molecules between two meta-stable orientations. A positive field of 2-4 V leads to this local change in the molecular arrangement, while a field larger than 4 V restores the original geometry.
authors.affiliation: Leibniz Universität Hannover, Institut für Festkörperphysik, Abteilung ATMOS, Appelstraßsse 2, D-30167 Hannover, Germany.
authors.forename: Fatih
authors.initials: F
authors.lastname: Kalkan
authors.forename: Michael
authors.initials: M
authors.lastname: Mehlhorn
authors.forename: Karina
authors.initials: K
authors.lastname: Morgenstern
mesh_terms: D000327:Adsorption; D003300:Copper / Q000737:chemistry; D004247:DNA / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D013499:Surface Properties; D013941:Thymine / Q000737:chemistry*
chemical_list: D003300:Copper; D004247:DNA; D013941:Thymine