A new measuring procedure for data collection with a high-pressure cell on an X-ray four-circle diffractometer

From single crystals contained in a high-pressure device, only reflection intensities in a greatly restricted range of reciprocal space can be measured. Many of these intensities may be strongly influenced by systematic errors due to the high-pressure device, if the standard measuring procedures of a four-circle diffractometer are used. These procedures measure intensities only in the bisecting position. The development of a new `high-pressure' measuring procedure is reported, which allows automatic measurement of reflection intensities in the greatest possible areas of reciprocal space and correction in the data-collection procedure for the systematic errors due to the high-pressure cell. This means that the intensity data obtained with this procedure can be analysed with the common programs for structure investigation.