Crystal Structure Determination from X-Ray Powder Diffraction Data

摘要

Many crystalline materials cannot be prepared in a suitable form for conventional single-crystal diffraction studies, and hence the successful structure characterisation and rationalisation of these materials and their properties often relies on the ability to gain this information from powder diffraction data. Although the refinement stage of the structure determination process can be carried out fairly routinely, structure solution is associated with several intrinsic difficulties. However, the recent development of direct-space structure solution methods has enabled the study of a wide range of materials using powder diffraction data, many of structural complexity only made tractable by these advances in methodology. This paper aims to guide you through the structure determination from powder diffraction process, highlighting the application of direct-space methods (and the global optimisation techniques on which they are based), including experimental and structural considerations, and examples illustrating the impact that powder diffraction has had on the structural study of both organic and inorganic materials.