Our research activity involves the theoretical simulation of the structural, electronic, optical and transport properties of materials, surfaces, interfaces and nanostructures.
- ab-initio density functional theory (DFT)
- maximally localized Wannier functions (MLWFs) calculation
- semi-empirical tight binding (TB)
- effective-mass approximation and other effective models
- Quantum ESPRESSO: an integrated suite of computer codes for electronic-structure calculations and materials modeling at the nanoscale. It is based on density-functional theory, plane waves, and pseudopotentials
- Wannier90: a computer package for the computations of the maximally localized Wannier functions
- NWChem: a computer package for computing the properties of molecular and periodic systems
- Yambo: a computer package for many-body calculations in solid state and molecular physics
Main research topics
Spin-polarized quantum conductance of randomly hydrogenated zigzag graphene nanoribbons
Electronic and transport properties of graphene
Methods: DFT - MLWFs
Short description: we study the electronic and transport properties of graphene, graphene nanoribbons and carbon nanotubes from first principles. Special attention is given to the effect of the presence of defects and of (edge or bulk) functionalization.
A view of the (4-dimethylaminopyridyl) bis(acetylacetato)zinc(II) organic crystal
Organic and hybrid organic-inorganic materials
Methods: DFT - GW
Short description: Structural, electronic and optical properties of hybrid organic-inorganic perovskitic materials with chemical formula ABX3 (A = monovalent cation at the centre of the unit cell, B = Sn, Pb and X = Cl, Br, I). Piezoelectricity in organic crystals, using the modern theory of polarization.
A model of a TiO2 (anatase)-SrTiO3 interface
Metal oxide surfaces and nanostructures
Short description: we study the structural, electronic and optical properties of: TiO2, SnO2 and ZnO surfaces; TiO2 nanowires and nanocrystals, for sensor applications, photocatalysis, new generation solar cells. Among the results, we cite: the role played by the size and surface passivation in TiO2 nanostructures; the theoretical assessment of the TiO2 (110) surface reconstruction; the explanation of the photoluminescence spectra of SnO2 nanobelts.
Organic coverage of the silicon (100) surface
Organic adsorbates on semiconductor/metallic surfaces
Short description: We have studied the covalent modification of the silicon (100) surface from first principles. Ethylene, cyclopenthene and a class of its derivatives have been chosen as test cases to correlate the surface structural and electronic properties changes to the properties of the adsorbate. The results show the possibility of surface properties (e.g. work function) engineering through a suitable choice of the adsorbate. Currently, we are extending our study to metal/organic interfaces.
The Si293H172 silicon nanocrystal
Methods: DFT, Tight Binding, Thomas Fermi
Short description: The structural and the optical properties of silicon nanocrystals are investigated with both the DFT and the tight binding methods. Doping and codoping together with the screening of the impurity potentials are studied with both DFT and Thomas Fermi.
XXXX N. Marzari (MIT) XXXX University of Napoli, Chemistry Department - S. Ossicini, E. Degoli (S3-CNR and University of Modena e Reggio Emilia) XXXX Department of Chemistry, University of Napoli "Federico II"