Caratterizzazione strutturale e funzionale di magneti molecolari supportati su superficie

The magnetic proprieties of cyclic complexes of paramagnetic transition-metal ions have attracted great interest in the last few years. In particular, some of these have been proposed as qbits candidates. For this reason, a possible molecular nanomagnet is reported in this work, i.e. the UHV-sublimated Cr10piv wheel on metallic substrates. The deposition on Ag(110), Cu(111) and Au(111) has been characterized by means of STM and XPS from a chemical and structural point of view. The analysis reveals that the molecules retain their structural integrity with a quasi-hexagonal self-assembly in a long-range-ordered array. Using the XAS & XMCD techniques we studied other proprieties, like magnetic anisotropies and magnetic moment as a function of the different substrates and layer thicknesses. Results for different samples are shown: 1ML Cr10/Au(I), 1ML Cr10/Au(II), (prepared to check the experimental reproducibility), 1MultiL Cr10/Au, and 1ML Cr10/Cu. The values for ms, mL and mtot were obtained by applying the sum rules to the different samples. The analysis demonstrates that the molecules show negligible anisotropy and do not manifest hysteresis (within experimental resolution). Finally, it was found that the deposited Cr10piv molecules exhibit an S=15 ground state, different from the S=9 found in the bulk complex.