THE USE OF CCD-DETECTORS IN 'SMALL MOLECULE' CRYSTALLOGRAPHY

Martin Nieger

Institut für Anorganische Chemie der Universität, Gerhard-Domagk-Str. 1, D-53121 Bonn E-mail: NIEGER@OC3062.CHEMIE.UNI-BONN.DE

Keywords: CCD-Detector, small molecule crystallography, four-circle diffractometer, data collection, refinement

Recently, there has been rapid development of area detector systems, e.g. image plate detectors or CCD-detectors. These area detector systems were developed for use in biocrystallography, but nowadays they are also applied in crystallography of 'small molecules' (less than 200 non hydrogen atoms in the asymmetric unit). In particular the CCD-detector systems were developed for the X-ray structure analysis of small molecules using sealed-tubes or rotating anode X-ray source and Mo radiation.

Nowadays, CCD-detector systems seem to become the 'state of the art' tool for 'small molecule' crystallography, and they are used in an increasing number of laboratories. Now it is possible to collect data and solve and refine a structure in several hours instead of several days, and X-ray crystal structure determination becomes not only a powerful but also a fast analytical tool for chemists.

Here, the results of the X-ray structure analyses of four typical organic and organometallic structures will be discussed. The data were collected using Bruker and Nonius CCD-detector systems and four-circle diffractometers.