Metal bis-1,2-dithiolene complexes in conducting or magnetic crystalline assemblies

Crystalline materials studied for their conducting or magnetic properties based on metal complexes of 1,2-dithiolene ligands are discussed emphasising the wide diversity of ligands now available and the variety of materials prepared from these. Complexes have been prepared using electronically delocalised dithiolene ligands where the core complex is extended with units such as thioethers, aromatics, tetrathiafulvalene (TTF) and other heterocycles to explore the influence of these variations on the solid-state structures and properties derived from them. Although superconductivity in dithiolene complexes has so far been limited to [M(dmit)(2)](x-) salts. other ligand systems have given rise to numerous conducting and metallic salts and have proven informative in rationalising the criteria for design of the molecular units, Novel material properties have been observed in systems such as hybrid conducting I magnetic materials and mixed dithiolene-metallocene salts. In particular, highly conducting and metallic single-component materials have recently been found uniquely within materials based on metal-bis-1,2-dithiolene complexes. Magnetic materials containing dithiolene-complex building blocks have yielded systems Such as ferromagnets, ferrimagnets, metamagnets and spin ladders in addition to other model systems suitable for the study of magnetic ordering. These can involve systems where the dithiolene complex is the only paramagnetic component in addition to more complex systems involving other types of building block. (C) 2002 Elsevier Science B.V. All rights reserved.