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We report transport measurements through a single-molecule magnet, the Mn 12 derivative Mn 12 O 12 O 2 C-C 6 H 4 -SAc 16 H 2 O 4 , in a single-molecule transistor geometry. Thiol groups connect the molecule to gold electrodes that are fabricated by electromigration. Striking observations are regions of complete current suppression and excitations of negative differential conductance on the energy scale of the anisotropy barrier of the molecule. Transport calculations, taking into account the high-spin ground state and magnetic excitations of the molecule, reveal a blocking mechanism of the current involving nondegenerate spin multiplets.

The present work reports the synthesis and the characterization of cobalt oxide thin films obtained by chemical vapor deposition (CVD) on indium tin oxide (ITO) substrates, using a cobalt(II) β-diketonate as precursor. The complex is characterized by electron impact mass spectrometry (EI-MS) and thermal analysis in order to investigate its decomposition pattern. The depositions are carried out in a cold wall reactor in the temperature range 350-500 °C at different oxygen pressures, to tailor film composition from CoO to Co 3 O 4 . The crystalline nanostructure is evidenced by X-ray diffraction (XRD), while the surface and in-depth chemical composition is studied by X-ray photoelectron (XPS) and X-ray excited auger electron spectroscopy (XE-AES). Atomic force microscopy (AFM) is employed to analyze the surface morphology of the films and its dependence on the synthesis conditions. Relevant results concerning the control of composition and microstructure of Co-O thin films are presented and discussed.

Hy wire: Supported Cu(2)O nanosystems and CuO nanowires obtained by chemical vapor deposition were used in the photocatalytic splitting of methanol/water solutions to produce hydrogen. The results obtained with these systems open appealing perspectives for the clean conversion of sunlight into storable chemical energy.