title: Morphological investigation of Mn12 single-molecule magnets adsorbed on Au(111).
abstract: We report on the adsorption of Mn(12) single-molecule magnets bearing external biphenyl groups on Au(111) surfaces after a simple dipping procedure. Topographic AFM images confirm that the biphenyl groups favor the adsorption of the molecules without the need of functionalization with thiols or thioether groups. The first formed molecular layer covers homogenously the whole surface, whereas further growth takes place mostly in the form of molecular wires (or aggregates) and, occasionally, as molecular islands. Interestingly, the Mn(12) core is preserved for all the cases, although its aggregation state appears to influence significantly the rigidity of the molecular aggregates. Force-volume imaging experiments have demonstrated that molecules at the second layer are stiffer, that is, more rigid, than the molecules lying at the background layer. This fact clearly reveals that the interplay of attractive and repulsive forces between molecules and the molecule-surface interaction modulate the mechanical properties of the Mn(12) single-molecule magnets upon grafting. These results are very important to understand how surface-induced morphological deformations can modify the magnetic properties of these molecular systems on the translation from the macroscopic to a surface.
authors.affiliation: Instituto de Ciencia de Materiales de Madrid (CSIC), Madrid, Spain.
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Otero
authors.forename: Emi
authors.initials: E
authors.lastname: Evangelio
authors.forename: Celia
authors.initials: C
authors.lastname: Rogero
authors.forename: Luis
authors.initials: L
authors.lastname: Vázquez
authors.forename: Jordi
authors.initials: J
authors.lastname: Gómez-Segura
authors.forename: José Angel Martín
authors.initials: JA
authors.lastname: Gago
authors.forename: Daniel
authors.initials: D
authors.lastname: Ruiz-Molina
mesh_terms: D000327:Adsorption; D016880:Anisotropy; D006046:Gold / Q000737:chemistry*; D008280:Magnetics; D008345:Manganese / Q000737:chemistry*; D008422:Materials Testing; D018625:Microscopy, Atomic Force / Q000379:methods; D008956:Models, Chemical; D008968:Molecular Conformation; D015394:Molecular Structure; D036103:Nanotechnology / Q000379:methods; D012542:Scattering, Radiation; D013059:Spectrum Analysis, Raman / Q000379:methods; D013499:Surface Properties; D014965:X-Rays
chemical_list: D008345:Manganese; D006046:Gold