An Improved Gas Electron Diffractometer - The Instrument, Data Collection, Reduction and Structure Refinement Procedures

Berger R, Hoffmann M, Hayes SA, Mitzel NW. An Improved Gas Electron Diffractometer - The Instrument, Data Collection, Reduction and Structure Refinement Procedures. ZEITSCHRIFT FUER NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES. 2009;64(11-12):1259-1268.The improvement of a Balzers Eldigraph KD-G2 gas-phase electron diffractometer, previously operated at the University of Tubingen, is reported. The diffractometer was equipped with a state-of-the-art telefocus electron gun, and high-energy radiation-sensitive imaging plates were introduced as detector system. A differential vacuum pumping system separating the diffraction chamber from the electron source was installed. A nozzle for the evaporation of compounds in a temperature range from 25 to 400 degrees C was constructed and its functionality proven by the structure determination of quinoline. Calibration, data reduction and structure refinement using standard procedures in connection with a selection of literature-known programs are described. The gas-phase structure of quinoline was determined, discussed and compared with ab initio and solid-state X-ray diffraction results