Structure determination from powder diffraction data using a new intensity extraction algorithm

A method is proposed for extracting the relevant structural information from powder diffraction data. The pattern is fitted and a reduced number of intensity values, called `pseudo-intensities', are extracted and used as a substitute for the full pattern in the structure determination algorithm. Since the number of pseudo-intensities is one order of magnitude smaller than the number of data points in the experimental data, the calculation of the agreement factor (R_wp), and hence the evaluation of a trial structure, is carried out more quickly. The method consists of a procedure for stripping out the influence of the profile fit from the full pattern R_wp factor, leaving just the important intensity information needed in the structure determination process.