STRUCTURE DETERMINATION USING CCD AREA DETECTOR - HOW SMALL A CRYSTAL IS TOO SMALL? Nigam P. Rath, Department of Chemistry, University of Missouri-St. Louis, 8001 Natural Bridge Road, St. Louis, MO 63121-4499, USA.

A Siemens CCD area detector system has been used to collect data on several very small crystals and their structure solution and refinement achieved by using SHELXTL 5.0 programs for structure determination. In some cases, structure has been re-determined using a bigger crystal and a comparison of results will be presented.

Diffraction data has been collected on the same crystal for organic and organometallic compounds using point detector diffractometer (Siemens P4) and CCD area detector system for comparison of structural results. Advantages and disadvantages of both the detector types will be discussed. Efforts are underway to develop data collection strategies for small crystals and weak diffractors for use with CCD area detector system. Our experience with the area detector system for small molecule structure determination, both high-points and pitfalls, will be presented.