Tetracyano-, tricyanomethanide-, and dicyanamide-based molecular magnets

Three distinct classes of molecule-based magnets have been isolated and characterized by several physical techniques such as magnetic susceptibility, specific heat, and neutron diffraction. These new materials consist of cyano and polycyano C(CN)₃- and N(CN)2-ligands bridged via paramagnetic transition metal centers to afford several novel inorganic structure-types. In some materials, interpenetration of a second equivalent lattice occurs. Among these are three-dimensional diamond, rutile and ReO₃-type networks that present a wide range of cooperative magnetic behavior including ferro, antiferro-, and weak ferromagnetism with ordering temperatures as high as 47 K. Non-classical behavior such as spin frustration was also observed in some examples. Various theoretical models were also employed to elucidate intra- and intermolecular exchange parameters.