Valdis Corradini

His research activity is devoted to the magnetic, structural and electronic investigation of low-dimensional metallorganic systems grown on metallic or semiconducting surfaces. He developed new strategies for the direct and indirect grafting of properly functionalized Molecular-Nano-Magnets (MNM) on suitable surfaces, exploiting the controlled deposition from solid, liquid or vapor phase. The aim is to verify how the main properties of the molecule are modified by the reduced dimensionality and by the interaction with the surface. Fields of his research activity:

• We have investigated the electronic and magnetic properties of LnPc2 molecules UHV-deposited on a graphene/Ni(111) substrate and how they modify when an Au-layer is intercalated between Ni and graphene. X-ray absorption spectroscopy (XAS), and linear and magnetic circular dichroism (XLD and XMCD) were used to characterize the systems and probe the magnetic coupling between LnPc2 molecules and the Ni substrate through graphene. Two types of LnPc2 molecules (Ln = Tb, Er) with a different magnetic anisotropy (easy-axis for Tb, easy-plane for Er)
• New families of MNMs with huge Magnetocaloric Effect (MCE) like Fe14 Gd4Ni8 and Gd4. He developed a new procedure to derive the entropy variation from the XMCD signal. It is possible to monitor if the MCE is preserved at the single molecule. This demonstrates, for the first time, that an important contribution to magnetic refrigeration is an intrinsic molecular property.
• The family of Cr8 antiferromagnetic rings and in particular the heterometallic Cr7Ni ring which is supposed to be particularly promising as “q-bit” for the implementation of a quantum information processing.
• Double-decker phthalocyaninato lanthanide (PcTbPc) have a long magnetization relaxation time as an intrinsic molecular property, and can act as a magnet at single-molecular level with a blocking temperature around 20 K. We have investigated the interaction between two lanthanides in a Triple-decker (Pc-Tb-Pc-Dy-PC).
• Investigation of organic self-assembled low dimensional systems on metallic surfaces. This activity is devoted to understand fundamental aspects of organic molecule interactions at surfaces, from the early stages of hybrid organic-inorganic interface formation to the creation of new 1D and 2D “organic surfaces” controlled by functionalization.
His experimental activity is performed both on-campus and at large scale facilities, to get advantage of the very powerful techniques relying on synchrotron radiation. He got experience in the structural and electronic investigation by exploiting Scanning Tunneling Microscopy (STM), Low Energy Electron Diffraction (LEED), Photoemission Spectroscopies (XPS, UPS), High-Resolution Electron Energy Loss (HREELS), X-ray absorption (XAS) and Resonant Photoemission (ResPES) spectroscopies. The magnetic and orientational properties are studied by Circular Magnetic Dichroism (XMCD) and Linear Dichroism (XLD).