2-DIMENSIONAL DETECTOR SOFTWARE - FROM REAL DETECTOR TO IDEALIZED IMAGE OR 2-THETA-SCAN

Detector systems introduce distortions into acquired data. To obtain a ccurate angle and intensity information, it is necessary to calibrate, and apply corrections. Intensify non-linearity, spatial distortion, a nd non-uniformity of intensity response, are the primary consideration s. It is better to account for the distortions within scientific analy sis software, but often it is more practical to correct the distortion s to produce 'idealised' data. Calibration methods and software have b een developed for single crystal diffraction experiments, using both a pproaches. For powder diffraction experiments;the additional task of c onverting a two-dimensional image to a one-dimensional spectrum is use d to allow Rietveld analysis. This task may be combined with distortio n correction to produce intensify information and error estimates. Hig h-pressure experiments can introduce additional complications and plac e new demands on software. Flexibility is needed to be able to integra te different angular regions separately, and to produce profiles as a function of angle of azimuth. Methods to cope with awkward data are de scribed, and examples of the techniques applied to data from high pres sure experiments are presented.