Recent developments and prospects of X-ray powder diffraction methods

13 Recent developments and prospects of X-ray powder diffraction methods. In the preceding paragraph a few comments have been made about diffractometry and its uses in the analysis of materials. However it is not possible to give here an account of this subject its principles and underlying theories, its experimental techniques and 

Recent developments and prospects of these methods have been discussed in a chapter by Schneider et al. (2001). It was underlined that these methods are widely applied for the characterization of crystalline materials (phase identification, quantitative analysis, determination of structure imperfections, crystal structure determination and analysis of 3D microstructural properties). Phase identification was traditionally based on a comparison of observed data with interplanar spacings and relative intensities (d and T) listed for crystalline materials. More recent search-match procedures, based on digitized patterns, and Powder Diffraction File (International Centre for Diffraction Data, USA.) containing powder data for hundreds of thousands substances may result in a fast efficient qualitative analysis. The determination of the amounts of different phases present in a multi-component sample (quantitative analysis) is based on the so-called Rietveld method. Procedures for pattern indexing, structure solution and refinement of structure model are based on the same method. 

The calculated intensities depend on several parameters which may be refined and defined these include the structural characteristics (the cell parameters, see Chapter 3) of the phase, its quantity in a multiphase sample, etc. 

In a paper by Albinati and Willis (1982) the application of the Rietveld method in neutron and X-ray powder diffraction was discussed considering the different experimental techniques of obtaining the diffraction patterns. For a detailed description of the method and its applications see a reference publication (Young 1995). See also Jenkins and Snyder (1996). A frequently used calculation program for the 

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