I am having a mixed phase system I want to index a ring pattern of electron diffraction pattern but I am unable to find the value matching. please any one explain. I am attaching here JCPDS of both phases (anatase and Monoclinic), Refined XRD pattern also and electron diffraction pattern image. Please suggest any literature and how to solve it
calculate d spacing for each ring ...then compare with the d spacing of standard data (of possible phases). and index the ring with which it is matching. How you are calculating the d spacing. Are you using any software? like Gatan etc
Theoretically, you could even add all intensities along the rings so that a diffractogram results which would look like measured by XRD. There is perhaps software available for Debye-Scherrer films, look at CCP14 web site. The major problem is the film distance which scales the 2theta values significantly. Also texture software uses a comparable algorithm if they apply 2D detectors.
The interpretation of the different phases is then comparable to the identification using an x-ray diffractogram (only using the wave length of electrons...a further limitation), with all advantages and disadvantages.
Please keep in mind that, no matter what method or software you used for the calculating the d-spacing from the SAED, the scale is possibily without calibration by the standard crystal. So, you can just calcalute the distance ratio between two rings, and match the ratios to the XRD data base.
For measuring the d-spacing using SAED pattern, firstly you have to draw a ring pattern over the diffraction points (planes). Now calculate the radius of each ring from the center of SAED pattern. Thereafter, you can calcalute the distance ratios between two rings successively, and match these ratios to the d-spacing values correspond to each plane using XRD data and compare with the d spacing of standard data. At last you can index the ring which is closely matched.
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