With XRD reference data, we can check the identity of the salts. Hence can anybody share the XRD data for certain phase change materials like NaNO3,KNO3,Ca(NO3)2 and their mixtures? Is there any weblink having XRD data outputs of general materials?
Knowing the structural information of your phases (space group, lattice parameters and atomic positions) you can calculate the powder diffraction patterns with some free softwares (Powder Cell for example). Otherwise CheckCell requires only tha space group and lattice parameters. In this case the intensities of the reflections are not reliable but are instead the peak positions.
Marcella is right: you can calculate any phase inplementing substitutions or occupations, adapting the lattice parameters etc by programs like PowderCell. In fact, all refinement programs like Fullprof, Topaz, Autoquant etc are based on this general approach: using the unit cell data and assuming an unlimited perfect lattice for calculation of the "ideal" powder diffraction pattern. The only assumption is related to the intensity distribution within each peak as function of the Bragg angle. This will change the visible peak hight and/or overlapping of peaks, but in fact the intensity under the peak will always be identical (for a certain diffraction geometry like Bragg-Brentano).
Crystallography Open Database - COD ( http://www.crystallography.net/search.html ) is a good place to look for structural information of virtually any phase. Then, you can use the structural information found there to simulate the powder diffraction patterns of the phases of interest (example PowderCell like it was suggested by Marcella Bini). Furthermore, you can download the structural information as a single file (Crystallografic Information File - CIF). CIF file is recognized by most of the XRD software.
CrsytalMaker can open CIFs, and in combination with CrsytalDiffract lets you visualize the structure of phases and also simulate the XRD patterns (both powder and single crystal). However, both of the software are commercial (by CrystalMaker Software Ltd.).
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