Metal-Metal Bonded Compounds of the Transition Metals

Iowa State University, Ames IA

Investigators

Abstract

This project explores the synthesis and physical and chemical characterization of a new class of materials, viz., ternary chalcogenides of the group 3 and group 4 transition and lanthanide metals. Many of these condensed cluster phases appear to be uniquely stabilized by strongly bound, late transition metals as interstitials in nominal clusters of the early metals, which is a new concept in solid state chemistry to be explored in this project. These cluster-interstitial combinations also allow insight into local interactions present around impurities in enigmatic intermetallic and pure metal systems, which is a new direction in chemistry. Physical properties of these will be defined by crystal structure studies, electronic conductivity, and magnetic susceptibility measurements, and with parallel extended-Hckel and density functional theory (band) calculations. Explorations for new examples of aperiodic quasicrystals and a new method for their direct structural definition are also planned. These studies afford advanced students training along new frontiers in techniques and chemistry. Participating undergraduate, graduate, and postdoctoral students will get valuable training and experience in advanced methods in solid state chemistry. Half of the personnel have been women in recent years, and the proportion is presently two-thirds. The discovery and development of new materials, utilizing synthetic explorations to uncover new and unprecedented solid compounds, structures and properties is crucial to advancing materials science. Successful syntheses often involve specialized techniques, conditions, and exotic containers that are not widely employed and, since the availability of new materials is a high priority in both industry and academia, students trained in these areas typically compete very well in the job market.