CRYSTAL-STRUCTURE DETERMINATION FROM POWDER DIFFRACTION DATA

A wide range of important crystalline solids cannot be prepared in the form of single crystals of suitable size and quality for structural c haracterization by conventional single-crystal X-ray diffraction metho ds. The development of techniques for crystal structure determination from powder diffraction data is clearly important for allowing the str uctural characterization of such materials. Although the structure ref inement stage of the structure determination process can now be carrie d out fairly routinely using the Rietveld profile refinement technique , structure solution directly from powder diffraction data is associat ed with several intrinsic difficulties. The article surveys the field of crystal structure determination from powder diffraction data. Parti cular emphasis is given to the challenging structure solution stage of the structure determination process, with illustrative case studies h ighlighting the features of each of the main methods that are currentl y used for structure solution from powder diffraction data. The curren t scope and future potential of powder diffraction as an approach for crystal structure determination are discussed, and contemporary applic ations of this approach across several disciplines within materials ch emistry are reviewed.