Modern magnetic chemistry of exchange clusters

The review concerns the state-of-the-art in studies on the magnetic chemistry of exchange clusters (polynuclear transition-metal complexes in which the unpaired electrons of particular sites are involved in magnetic exchange due to both direct or indirect, via bridging ligands, interactions of their wave functions). Particular emphasis is placed on (i) theoretical models that can be used to interpret experimental data in terms of the effective Hamiltonians and chemical bonding theory and (ii) molecular nanomagnets (complexes containing a large number of magnetic atoms and possessing unusual properties).