Building Layers within Layers - Topotactic Reaction Strategies for the Assembly of Metal-Anion Layers within Receptive Hosts

University Of New Orleans, New Orleans LA

Investigators

Abstract

Low temperature (less than 500 degrees Centegrade) synthetic strategies will be developed to direct the preparation of new solid-state materials. By exploiting ion exchange and intercalation methods, metal-anion layers (transition-metal halide, oxide, chalcogenide, etc.) will be assembled within receptive host compounds. Emphasis will be placed on multistep reaction processing where the sequential application of exchange/intercalation methods will lead to new intricately layered products. A complementary focus area will be the preparation of new host materials receptive to low temperature topotactic manipulation -- new layered oxide hosts based on perovskite and Sillen structure types will be sought. The detailed characterization of new compounds will be a particularly important aspect of this project. Topotactically prepared materials, as well as new hosts, are expected to demonstrate significant structural, magnetic, and electronic properties, especially in the case of mixed-valence compounds. %%% This project will have both a broad scientific and educational impact. In terms of the scientific impact, this will be seen in the long term with the development of an extended series of low temperature reaction strategies. A comprehensive library of reactions can be envisioned that would allow for the directed, rational synthesis of new nonmolecular target compounds with specific structural, electronic and magnetic features. Such extensive capabilities would mirror those currently available to synthetic organic chemists. With respect to the educational impact, efforts here will focus on the training of students and presentations to the local community. Undergraduate and graduate students will be involved in all aspects of the research component of this program. This experience will provide them with valuable training in the synthesis and characterization of new materials as well as the presentation and publication of scientific data. A further aspect of this component is the involvement of international students where undergraduate and/or graduate students from France will work in this research group in the laboratory; this effort will serve to promote solid-state chemistry at the international level. Finally, to communicate topics on solid state and materials chemistry to nonscientists in the local community, New Orleans public schools (K-12) will be visited to give lectures and demonstrations on concepts pertinent to solid state and materials chemistry.