A5076721992- Molecular Junctions and Nanostructures
- Graphene research and applications
- Advanced Chemical Physics Studies
- Surface and Thin Film Phenomena
- Surface Chemistry and Catalysis
- Quantum and electron transport phenomena
- Magnetic properties of thin films
- Electron and X-Ray Spectroscopy Techniques
- Physics of Superconductivity and Magnetism
- 2D Materials and Applications
- Fullerene Chemistry and Applications
- Quantum, superfluid, helium dynamics
- Semiconductor materials and devices
- Advanced Physical and Chemical Molecular Interactions
- Spectroscopy and Quantum Chemical Studies
- Topological Materials and Phenomena
- Catalytic Processes in Materials Science
- Chemical and Physical Properties of Materials
- Advanced Materials Characterization Techniques
- nanoparticles nucleation surface interactions
- Porphyrin and Phthalocyanine Chemistry
- Carbon Nanotubes in Composites
- Catalysis and Oxidation Reactions
- Electrochemical Analysis and Applications
- Iron oxide chemistry and applications
University of Milan
2016-2025
Istituto Nazionale di Fisica Nucleare, Sezione di Milano
2021-2023
European Theoretical Spectroscopy Facility
2014-2021
Mylan (Switzerland)
2014-2021
European Telecommunications Standards Institute
2021
University of Milano-Bicocca
2008-2020
Milano University Press
2014-2020
Mylan (South Africa)
2018
National Interuniversity Consortium for the Physical Sciences of Matter
2008-2014
Elettra-Sincrotrone Trieste S.C.p.A.
2014
QUANTUM ESPRESSO is an integrated suite of computer codes for electronic-structure calculations and materials modeling, based on density-functional theory, plane waves, pseudopotentials (norm-conserving, ultrasoft, projector-augmented wave). The acronym stands opEn Source Package Research in Electronic Structure, Simulation, Optimization. It freely available to researchers around the world under terms GNU General Public License. builds upon newly-restructured that have been developed tested...
Quantum ESPRESSO is an integrated suite of open-source computer codes for quantum simulations materials using state-of-the art electronic-structure techniques, based on density-functional theory, perturbation and many-body within the plane-wave pseudo-potential projector-augmented-wave approaches. owes its popularity to wide variety properties processes it allows simulate, performance increasingly broad array hardware architectures, a community researchers that rely capabilities as core...
Line them up: Metal–organic chains (see scanning tunneling microscopy image) have been created in situ by self-organized growth at a metal surface under ultrahigh vacuum. These 1D arrangements of centers (Fe, Cu), regularly spaced organic linkers such as trimesitylic acid, open new possibilities for the study low-dimensional magnetism.
The adsorption of trimesic acid (TMA) on Cu(110) has been studied in the temperature range between 130 and 550 K for coverages up to one monolayer. We combine scanning tunneling microscopy (STM), low-energy electron diffraction (LEED), reflection absorption infrared spectroscopy (RAIRS), X-ray photoemission (XPS), density functional theory (DFT) calculations produce a detailed phase diagram TMA/Cu(110) system as function molecular coverage substrate temperature. identify quite complex set...
Silicene, a honeycomb lattice of silicon, presents particular case allotropism on Ag(111). Silicene forms multiple structures with alike in-plane geometry but different out-of-plane atomic buckling and registry to the substrate. Angle-resolved photoemission first-principles calculations show that these silicene structures, (4×4), (√13×√13)R13.9°, (2√3×2√3)R30° periodicity, display similar electronic bands despite structural differences. In all cases interaction substrate modifies states,...
We report the incorporation of substitutional Mn atoms in high-quality, epitaxial graphene on Cu(111), using ultralow-energy ion implantation. characterize detail atomic structure a single carbon vacancy and quantify its concentration. In particular, we are able to determine position with respect Moiré superstructure (i.e., local graphene-Cu stacking symmetry) sublattice; out-of-plane direction, found be slightly displaced toward Cu surface, that is, effectively underneath layer. Regarding...
Abstract The synthesis of new Xenes and their potential applications prototypes have achieved significant milestones so far. However, to date the realization Xene heterostructures in analogy with well known van der Waals remains an unresolved issue. Here, a heterostructure concept based on epitaxial combination silicene stanene Ag(111) is introduced, how one layer enables another different nature grow top demonstrated. Single‐phase (4 × 4) synthesized using as template, grown other way...
Magnonics is a rapidly growing field that nowadays broadly recognized as paradigm shift for information and communication technologies. In this context, antiferromagnetic materials are particularly relevant due to the lack of stray fields their faster dynamics, with frequencies in THz range longer spin relaxation times. Herein, we investigate chemical tuning magnons prototypical transition metal oxide through creation hybrid heterostructure formed by an Fe-phthalocyanine layer over NiO(001)...
The issue of tuning the relative height first two dehydrogenation barriers methane (CH4 → CH3 + H and CH2 H) is addressed using density-functional theory. It shown that combination a very active reaction centersuch as Rhwith more inert substratesuch Cu(111)may hinder second step with respect to first, thus resulting in reverse natural order barriers' heights.
We report a combined experimental and theoretical study of the optical response epitaxial silicene on silver. The silicene/Ag(111) ultraviolet-visible absorption spectra, which turn out to be strongly nonadditive, are analyzed in framework ab initio calculations. Electronic transitions involving silver states found provide huge contributions silicene, compatible with strong Si-Ag hybridization. results independent specific configuration also worked for thin amorphous silicon. This points...
Self-assembled monolayers (SAMs) of N-heterocyclic olefins (NHOs) have been prepared on Au(111) and their thermal stability, adsorption geometry, molecular order were characterized by X-ray photoelectron spectroscopy, polarized absorption scanning tunneling microscopy (STM), density functional theory (DFT) calculations. The strong σ-bond character NHO anchoring to Au induced high geometrical flexibility that enabled a flat-lying geometry via coordination gold adatom. was utilized further...
The dependence of the near-edge X-ray absorption fine structure (NEXAFS) spectrum molecules on photon electric field direction is investigated by means first-principles simulations based density functional theory with transition-potential approach. In addition to well-known NEXAFS resonances orientation respect molecular plane, we demonstrate that for planar sufficient in-plane anisotropy such as pentacene a dichroic effect found splitting σ* resonance function azimuthal in plane. length...
Long linear carbon nanostructures based on sp-hybridization can be synthesized by exploiting on-surface synthesis of halogenated precursors evaporated Au(111), thus opening a way to investigations surface-science techniques. By means an experimental approach combining scanning tunneling microscopy and spectroscopy (STM STS) with ex situ Raman we investigate the structural, electronic vibrational properties polymeric sp-sp2 atomic wires composed sp-carbon chains connected through phenyl...
Graphdiyne, atomically thin two-dimensional (2D) carbon nanostructure based on sp-sp2 hybridization is an appealing system potentially showing outstanding mechanical and optoelectronic properties. Surface-catalyzed coupling of halogenated sp-carbon-based molecular precursors represents a promising bottom-up strategy to fabricate extended 2D systems with engineered structure metallic substrates. Here, we investigate the atomic-scale electronic vibrational properties graphdiyne-like...
The synthesis of silicene by direct growth on silver is characterized the formation multiple phases and domains, posing severe constraints spatial charge conduction towards a technological transfer to electronic transport devices. Here we engineer silicene/silver interface two schemes, namely, either through decoration Sn atoms, forming an Ag2Sn surface alloy, or buffering with stanene layer. Whereas in both cases Raman spectra confirm typical features as expected from silicene, electron...
We have investigated the formation of scanning tunneling microscopy (STM) atomically resolved images $\text{Fe}(001)\text{\ensuremath{-}}p(1\ifmmode\times\else\texttimes\fi{}1)\text{O}$ surface. The latter is characterized by a high in-plane symmetry for both oxygen and iron atoms, thus representing very appealing template understanding how to distinguish between metal atoms in STM an oxidized report on occurrence corrugation reversal as function tip-sample distance, we use conclusions such...
We made use of synchrotron radiation to perform near edge X-ray absorption fine structure spectroscopy, NEXAFS, at the carbon K-edge perylene and perylene-tetracarboxylic-diimide, PTCDI. Reference spectra measured for isolated molecules in gas phase are compared with polarization dependent NEXAFS on highly oriented thin films order study symmetry molecular orbitals. The overlayers grown onto rutile TiO2(110) surface which large anisotropic corrugation effectively drives orientation, while...
The oxygen-saturated Fe(001)-$p(1\ifmmode\times\else\texttimes\fi{}1)$O surface has been used as a template to stabilize two-dimensional Cr oxides on Fe(001). deposition at 400 ${}^{\ensuremath{\circ}}$C leads two different well-ordered phases, depending the amount of deposited. In submonolayer regime novel $c(4\ifmmode\times\else\texttimes\fi{}2)$ overlayer self-assembles surface, saturating for coverage about $0.75$ monolayers. This phase becomes unstable higher coverages, when...
We measure direct multiphoton photoemission of the Au(111) surface state with 800-nm laser pulses. observe parabolic dispersion in angular distribution photoelectrons having absorbed between four and seven photons. The ${\mathbf{k}}_{\ensuremath{\parallel}}$ we can be explained terms Shockley-state replicas, a nascent hot electrons at above Fermi level. Moderate power densities, order $100\phantom{\rule{0.3em}{0ex}}\mathrm{GW}/\mathrm{cm}{}^{2}$, resulted large electron yields, indicating...
A remarkable enhancement of atomic diffusion is highlighted by scanning tunneling microscopy performed on ultrathin metastable body-centered tetragonal Co films grown Fe(001). The follow a nearly perfect layer-by-layer growth mode with saturation island density strongly dependent the layer which nucleation occurs, indicating lowering barrier. Density functional theory calculations reveal that this phenomenon driven increasing capability film to accommodate large deformations as thickness...
Abstract We predict the induction or suppression of magnetism in valence shell physisorbed and chemisorbed organic molecules on graphene occurring femtosecond time scale as a result core level excitations. For molecules, where interaction with is dominated by van der Waals forces system non-magnetic ground state, numerical simulations based density functional theory show that electrons relax towards spin polarized configuration upon excitation core-level electron. The depends efficient...
Alkali metal atoms are frequently used for simple yet efficient n-type doping of organic semiconductors and as an ingredient the recently discovered polycyclic aromatic hydrocarbon superconductors. However, incorporation dopants from gas phase into molecular crystal structures needs to be controlled well understood in order optimize electronic properties (charge carrier density mobility) target material. Here, we report that potassium intercalation pristine 3,4,9,10-perylenetetracarboxylic...
The surface reduction of rutile TiO2(110) generates a state in the band gap whose excess electrons are spread among multiple sites, making conductive and reactive. charge extraction, hence catalytic properties, depends critically on spatial extent redistribution, which has been hitherto probed by small molecules that recombine at oxygen vacancy (Ovac) sites. We demonstrate valence resonant photoemission (RESPES) very general extraction mechanism from reduced to an extended electron-acceptor...
The current study generates profound atomistic insights into doping-induced changes of the optical and electronic properties prototypical PTCDA/Ag(111) interface. For doping K atoms are used, as KxPTCDA/Ag(111) has distinct advantage forming well-defined stoichiometric phases. To arrive at a conclusive, unambiguous, fully understanding interface properties, we combine state-of-the-art density-functional theory calculations with differential reflectance data, photoelectron spectra, X-ray...