Marina Pivetta
École Polytechnique Fédérale de Lausanne
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Marina Pivetta.
Physical Review Letters | 2005
Elizabeta Ćavar; Marie-Christine Blüm; Marina Pivetta; F. Patthey; Majed Chergui; Wolf-Dieter Schneider
Using the highly localized current of electrons tunneling through a double barrier scanning tunneling microscope junction, we excite luminescence from a selected C60 molecule in the surface layer of fullerene nanocrystals grown on an ultrathin NaCl film on Au(111). In the observed fluorescence and phosphorescence spectra, pure electronic as well as vibronically induced transitions of an individual C60 molecule are identified, leading to unambiguous chemical recognition on the single-molecular scale.
Advanced Materials | 2016
Christian Wäckerlin; Fabio Donati; Aparajita Singha; Romana Baltic; Stefano Rusponi; Katharina Diller; F. Patthey; Marina Pivetta; Yanhua Lan; Svetlana Klyatskaya; Mario Ruben; Harald Brune; Jan Dreiser
TbPc2 single-molecule magnets adsorbed on a magnesium oxide tunnel barrier exhibit record magnetic remanence, record hysteresis opening, perfect out-of-plane alignment of the magnetic easy axes, and self-assembly into a well-ordered layer.
Angewandte Chemie | 2008
Marina Pivetta; Marie‐Christine Blüm; F. Patthey; Wolf-Dieter Schneider
Keywords: rubrene ; scanning probe microscopy ; self-assembly ; supramolecular chemistry ; Crystals ; Symmetry ; Graphite Reference EPFL-ARTICLE-161210doi:10.1002/anie.200704479View record in Web of Science Record created on 2010-11-30, modified on 2016-08-09
Optics Express | 2009
Frédéric Rossel; Marina Pivetta; F. Patthey; Wolf-Dieter Schneider
Tunneling electrons from a scanning tunneling microscope (STM) induce luminescence from C(60) and C(70) molecules forming fullerene nanocrystals grown on ultrathin NaCl films on Au(111). Intramolecular fluorescence and phosphorescence associated with the transitions between the lowest electronic excited state and ground state of C(70) molecules are identified, leading to unambiguous chemical recognition on the nanoscale. Moreover we demonstrate that the molecular luminescence is selectively enhanced by localized surface plasmons in the STM tip-sample gap.
New Journal of Physics | 2004
Fabien Silly; Marina Pivetta; Markus Ternes; F. Patthey; J. P. Pelz; Wolf-Dieter Schneider
The coverage-dependent self-organization of Ce-adatoms on a Ag(111) surface is studied by scanning tunnelling microscopy at temperatures ranging from 3.9 to 10 K. At a coverage of 0.03% of a Ce monolayer individual Ce-adatoms and Ce dimers are observed, the mutual interatomic distances of which are clearly related to multiples of the Fermi wavelength λF/2, reflecting surface-state-mediated electronic interactions. At a coverage of 0.2% the formation of chains and small islands with hexagonal structure prevails. At a coverage of 1% a hexagonal superlattice with a periodicity of 3.2 nm is observed. At a coverage of 2% the superlattice of Ce-adatoms is found to be compressed, showing an interatomic distance of 2.2 nm. At higher coverage the number of dimers increases considerably and the superlattice collapses into compact islands. An increase in the temperature towards about 10 K at a coverage of 1% also causes the collapse of the hexagonal Ce superlattice. These experimental findings are rationalized within the electron scattering model of Hyldgard and Persson, which specifically takes into account the electronic surface-state on Ag(111). The experimentally derived two-body interaction potential is able to account for the observed phenomena as a function of concentration and temperature.
Physical Review Letters | 2015
Susanne Baumann; Fabio Donati; Sebastian Stepanow; Stefano Rusponi; W. Paul; Shruba Gangopadhyay; Ileana G. Rau; Giulia E. Pacchioni; Luca Gragnaniello; Marina Pivetta; Jan Dreiser; Cinthia Piamonteze; Christopher P. Lutz; R. M. Macfarlane; B. A. Jones; Pietro Gambardella; Andreas J. Heinrich; Harald Brune
We report on the magnetic properties of individual Fe atoms deposited on MgO(100) thin films probed by x-ray magnetic circular dichroism and scanning tunneling spectroscopy. We show that the Fe atoms have strong perpendicular magnetic anisotropy with a zero-field splitting of 14.0±0.3 meV/atom. This is a factor of 10 larger than the interface anisotropy of epitaxial Fe layers on MgO and the largest value reported for Fe atoms adsorbed on surfaces. The interplay between the ligand field at the O adsorption sites and spin-orbit coupling is analyzed by density functional theory and multiplet calculations, providing a comprehensive model of the magnetic properties of Fe atoms in a low-symmetry bonding environment.
Journal of Chemical Physics | 2015
Marina Pivetta; Giulia E. Pacchioni; Edgar Fernandes; Harald Brune
We present the results of temperature-dependent self-assembly of dicarbonitrile-pentaphenyl molecules (NC-Ph5-CN) on Cu(111). Our low-temperature scanning tunneling microscopy study reveals the formation of metal-organic and purely organic structures, depending on the substrate temperature during deposition (160-300 K), which determines the availability of Cu adatoms at the surface. We use tip functionalization with CO to obtain submolecular resolution and image the coordination atoms, enabling unequivocal identification of metal-coordinated nodes and purely organic ones. Moreover, we discuss the somewhat surprising structure obtained for deposition and measurement at 300 K.
Journal of Physical Chemistry B | 2009
Marina Pivetta; Marie-Christine Blüm; F. Patthey; Wolf-Dieter Schneider
The growth of rubrene (C(42)H(28), 5,6,11,12-tetraphenylnaphthacene) multilayer islands up to a thickness of six layers on a Au(111) surface has been investigated by scanning tunneling microscopy. The molecules self-organize in parallel twin rows, forming mirror domains of defined local structural chirality. Each layer is composed of twin-row domains of the same structural handedness rotated by 120 degrees with respect to each other. Moreover, this structural chirality is transferred to all successive layers in the island, resulting in the formation of three-dimensional objects having a defined structural chirality. The centered rectangular surface unit cell differs from the one characteristic for the single-crystal orthorhombic phase.
ChemPhysChem | 2010
Marina Pivetta; Marie‐Christine Blüm; F. Patthey; Wolf-Dieter Schneider
Coverage-dependent self-assembly of rubrene molecules on different noble metal surfaces, Au(111) and Au(100), Ag(111) and Ag(100), is presented. On Au(111), the homochiral supramolecular assemblies evolve with increasing rubrene coverage from very small structures composed of a few molecules, to honeycomb islets, and to one-dimensional chains of supramolecular pentamers. At higher coverage, the racemic mixture of molecules forms close-packed islands. On Au(100), chains of pentamers and two different types of densely packed islands are formed. On the Ag surfaces, exclusively close-packed islands are created, independently of the rubrene coverage. Moreover, the role of the chiral nature of the molecules in the self-assembly process is discussed, as well as the existence of different molecular conformers depending on the supramolecular assembled phase. The observed differences and similarities reflect the influence of the electronic properties and the geometric structure of the various substrates on molecular self-assembly.
ACS Nano | 2016
Jan Dreiser; Giulia E. Pacchioni; Fabio Donati; Luca Gragnaniello; A. Cavallin; Kasper S. Pedersen; Jesper Bendix; Bernard Delley; Marina Pivetta; Stefano Rusponi; Harald Brune
We have studied Er(trensal) single-ion magnets adsorbed on graphene/Ru(0001), on graphene/Ir(111), and on bare Ru(0001) by scanning tunneling microscopy and X-ray absorption spectroscopy. On graphene, the molecules self-assemble into dense and well-ordered islands with their magnetic easy axes perpendicular to the surface. In contrast, on bare Ru(0001), the molecules are disordered, exhibiting only weak directional preference of the easy magnetization axis. The perfect out-of-plane alignment of the easy axes on graphene results from the molecule-molecule interaction, which dominates over the weak adsorption on the graphene surface. Our results demonstrate that the net magnetic properties of a molecular submonolayer can be tuned using a graphene spacer layer, which is attractive for hybrid molecule-inorganic spintronic devices.