PUB - Publikationen an der Universität Bielefeld

Properties of the manganese-based single-molecule magnet [(Mn6CrIII)-Cr-III](3+) are studied. It contains six Mn-III ions arranged in two bowl-shaped trinuclear triplesalen building blocks linked by a hexacyanochromate and exhibits a large spin ground state of S-t = 21/2. The dominant structures in the electron emission spectra of [(Mn6CrIII)-Cr-III](3+) resonantly excited at the L-3-edge are the L3M2,3M2,3, L3M2,3V and L3VV Auger emission groups following the decay of the primary p(3/2) core hole state. Significant differences of the Auger spectra from intact and degraded [(Mn6CrIII)-Cr-III](3+) show up. First measurements of the electron spin polarization in the L3M2,3V and L3VV Auger emission peaks from the manganese constituents in [(Mn6CrIII)-Cr-III](3+) resonantly excited at the L-3-edge near 640 eV by circularly polarized synchrotron radiation are reported. In addition spin resolved Auger electron spectra of the reference substances MnO, Mn2O3 and Mn-II(acetate)(2)center dot 4H(2)O are given. The applicability of spin resolved electron spectroscopy for characterizing magnetic states of constituent atoms compared to magnetic circular dichroism (MCD) is verified: the spin polarization obtained from Mn-II(acetate)(2)center dot 4H(2)O at room temperature in the paramagnetic state compares to the MCD asymmetry revealed for a star-shaped molecule with a (Mn4O6)-O-II core at 5 K in an external magnetic field of 5 T.