Photon cross-section data from X-Ray diffraction pattern measurements: Correction procedure evaluations

The feasibility of evaluating absolute differential cross-sections of coherently scattered X-rays by exploiting diffraction pattern measurements has been tested in the case of plastic and biological samples. The investigation takes into account three powder diffractometers with different irradiation facilities. The main relevant correction factors have been evaluated by means of Monte Carlo and computational algorithm approaches. A careful evaluation of the effect of non-monochromatic incident photon beams allows this procedure to be valid without resorting to sophisticated irradiation facilities. Moreover, in comparing the experimental data with the theory, it is shown that some assumptions usually made when calculating theoretical scattering cross-sections are not valid when a scattering angle ranging from forward to backscattering values is to be considered. These results, together with other usual instrumental corrections, permit us to evaluate the differential scattering cross-sections within acceptable uncertainties.