is equal The number of X-Ray peaks in XRD and the number of rings in the electron diffraction pattern by TEM for a same polycrystal thin film/powder sample?
The question is not clear. If with XRD you mean an XRPD pattern collected by a classical diffractometer with a point detector and with "number of rings" you refer to the rings observed by an area detector the answer is: for a given compound, using the same wavelength the number of "maxima" is the same in both cases in a fixed interval of teta Bragg angles.
Dear Giovanni ,
my means :
number of rings in the electron diffraction pattern using TEM is equal with The number of X-Ray peaks in XRD ?
For a given range of interplanar spacings (e.g between 10 and 1 Angstrom) the number of diffractions is the same; however, being diffractions intensities quite different for X-rays and electrons the number of very weak diffractions can be different for the two methods. Consequently, the number of observed peaks/rings may differ. Likely you can expect less X-ray peaks.
Dear Profossor,
if our sample be thin fim (thickness of thin fim in order x-ray wavelength) , so number of rings in the electron diffraction pattern using TEM is equal with The number of X-Ray peaks in XRD?
If you are measuring the same range of Q space, then the number of hkl rings will be the same. However, it is doubtful that you are measuring the same range of Q space with both x-rays and electrons, unless you are using extremely high energy x-rays and a large area detector.
As Lawrence pointed out, it's very unlikely that you will observe the same number of hkl rings in the two cases. The effect of diffraction in a TEM is comparable to having such a large radius of the Ewald sphere that the flat surface of the detector (or screen) may be considered to coincide with the surface of the sphere up to a fairly high diffraction angle, even without rocking the sample. It depends on the energy of the electrons (i.e. kV), hence their wavelength and it can be explained by the dynamic theory of diffraction. But this is beyond the scope of a simple answer to a simple question.
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