A traditional theme in the materials chemistry of inorganic solids has been the synthesis and characterization of crystal/chemical structures with interesting properties that directly affect the quality of human environments or that influence efforts in the research/development and manufacturing sectors of the economy. In our current research program these traditional interests have been fused with the emergent one of extensive molecular engineering of reactant materials so as to obtain by means of highly specific reaction conditions a solid product with closely-controlled compositional, structural and morphological parameters. A special feature of our group's efforts in this area has been to choose reactants whose structure and reactivity patterns offer some possibilities of elucidating the elementary steps in the formation of a particular solid. For example, when oxides or carbonates are employed as starting materials in the synthesis of SrFe12O19, a complex reaction path is followed which involves a perovskite intermediate and an unusual redox sequence for iron. When a metallo-organic/iron hydroxide reactant pair is employed, the reaction path proceeds through a single solid phase, which contains important structural elements of the final SrFe12O19 product; indeed the SrFe12O19 could be considered to be an exsolution product of the starting material. Studies on mixed-valence compounds [spinels, silicates (Ilvaite) and iron phosphates], naturally occurring glasses (tektites), inorganic phases in coals and novel permanent magnet oxides constitute significant aspects of our group's current efforts.
