HIGH-PRESSURE SYNTHESIS OF METASTABLE MATERIALS

This paper presents a review of the high pressure synthesis of metastable materials. Many solids synthesized at high pressure can be quenched to ambient conditions, where they may be thermodynamically metastable, yet remain indefinitely kinetically stable. Such routes to metastable solids have attracted much attention, because many of the most technologically important and useful materials are metastable. For geophysics, knowledge of the high pressure-high temperature chemistry of the materials that exist in the interior of the Earth and other planets is crucial to understanding their formation, structure, composition, and evolution. New synthetic opportunities have arisen in this area because of rapid advances in high pressure technology. Using preliminary results from our laboratory, the synthesis of materials at high pressures with modern diamond anvil cells and large volume techniques will be illustrated. (c) 1995 Academic Press, Inc.