Shadowing and absorption corrections of high-pressure powder diffraction data: toward accurate electron-density determinations.
The shadowing of the primary beam and of reflections from a powder crystal sample enclosed in a diamond-anvil high-pressure cell (DAC) is described for unrestricted data-collection procedures. The corrections account for the shadowing of the data measured with point- or area-detector diffractometers and can be applied for any containers of environment devices enclosing a powdered sample. The general procedure for correcting the powder diffraction data can be applied for analysing and optimizing diffractometric procedures of data collection and provides facilities for collecting high-pressure powder diffraction data with the DAC positioned optimally and rotated to counteract the preferred-orientation and particle-size effects, and to increase the resolution of data. The quadrature effects of numerical integration for the accuracy of computed corrections have been analysed.
Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60-780 Poznań, Poland. katran@amu.edu.pl
Andrzej
A
Katrusiak