W0282

A Straightforward Approach to Indexing and Integrating Reflections From Modulated Structures: The Structure of Lazurite. Lee M. Daniels¹, Jeffrey E. Post² and Christer Svensson³, ¹Rigaku/MSC, Inc., 9009 New Trails Dr., The Woodlands, TX 77381, ²National Museum of Natural History, Smithsonian Institution, Washington, DC 20560,³Materials Chemistry, Lund Univ., Lund, Sweden.

A straightforward, understandable approach to indexing and refining the unit cell will be described, including indexing on the main cell followed by the assignment of Q-vectors for the satellite reflections. As an example, the modulated structure of Lazurite will be described, along with the description of a multi-periodic structure (periodicities differ with direction). Reflections for Lazurite have been measured out to very high resolution (2theta = 140deg) with Mo radiation using a curved image plate detector, offering additional insight into the nature of the structure.