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[[Image:CdSeDiffractogram.JPG|thumb|left|Diffractogram of CdSe]] The figure to the left is a diffractogram of a sample of CdSe Quantum Dots given by an XRD test along with an overlay of the diffraction pattern of CdSe provided by the [http://en.wikipedia.org/wiki/International_Centre_for_Diffraction_Data International Center for Diffraction Data] (ICDD). The ICDD collects and maintains Powder Diffraction Files (PDFs) on most known elements and compounds, as the location and magnitude characteristic peaks found in XRD are unique to a particular material, identifying unknown materials and compounds is easy with an accurate enough diffractogram. The CdSe diffractogram to the left lines up pretty well with the CdSe PDF with respect to potential impurities or human/machine error. Particle size, interplaner spacing, and a number of other properties of a sample can be taken from XRD, using equations like the the [http://en.wikipedia.org/wiki/Bragg%27s_Law#Bragg_condition Bragg Equation] and the [http://en.wikipedia.org/wiki/Scherrer_equation Scherrer Equation] and other techniques as well. This approach would be most effective if a sample of ink was printed into a thin film to be used in a diffractometer. It would confirm whether or not the tested batch could or should be used well before it was used during manufacture.
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