Synthesis and Magnetic Investigations of New My-Carbamato-Metal Complexes and of Derived My-OH Compounds Using Directing Ligands

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A series of new spin bearing carbamato-metal complexes of the general formula [{M(O2NR2)n}m] (M = d- or f- block metals, nkleiner als1; mkleiner als2, R= pyridyl) will be synthesized using new sec.-amine ligands with directing groups R. The magnetic exchange interactions of this class of compounds will be investigated for the first time systematically. Departing from the obtained carbamato-metal complexes, the related µ-OH derivatives should be accessible by controlled hydrolysis reactions. This latter class of compounds exhibits strong structural similarity to the magnetically well-investigated class of large µ-OH clusters possessing a very high ground state spin arising from ferromagnetic interactions of the paramagnetic centres. Certain members of that class behave as "single molecular magnets" (SMM's) due to quantum tunnelling relaxation at rather low temperatures. Thus, magneto-structural property correlations of the newly synthesized carbamato-metal complexes and of their µ-OH derivatives will be studied in order to understand the factors that lead to high-spin ground states and magnetic anisotropy. Such correlations for a new class of compounds will be an essential contribution in the directed search for new molecule based magnets.