In XRD, for each peaks mentioned d (ang) and size? Is the d(ang) and size related to crystal size? Can i used them to calculate crystal size? I have used selected major peak intensity to calculate relative crystallinity as semi-quantative index of crystallinity, is it acceptable or i need to use other software? Thank you for your assist.
the d values are the spacing alues of the respective lattice planes. so the peak at approx 20 ° correspondence to a spacing of 4.25. This is not related to the crystal size. normally what you do is to calculate the integral width of a peak, let's say 001 by integration and division by the height. this values gives you the reciprocal crystallite size if you plot Int. vs s (scattering vector). form the values you have the FWHM would be mostly related to these technique but you have to consider the gaussian function is you use scherrer equation.
the crystallinity has nothing to do with the crystallite size as the amourphous phase only contributes a background and everything is in superposition. to get the crystallinity you have to separate the background from the peaks and compare the areas of both. this is only valid if both the crystalline and amorphous phase have the same scattering factors/densities. if this is not the case you may apply the internal standard method where you add certain amounts of a very high grystalline material and generate a calibration curve..
the d values are the spacing alues of the respective lattice planes. so the peak at approx 20 ° correspondence to a spacing of 4.25. This is not related to the crystal size. normally what you do is to calculate the integral width of a peak, let's say 001 by integration and division by the height. this values gives you the reciprocal crystallite size if you plot Int. vs s (scattering vector). form the values you have the FWHM would be mostly related to these technique but you have to consider the gaussian function is you use scherrer equation.
the crystallinity has nothing to do with the crystallite size as the amourphous phase only contributes a background and everything is in superposition. to get the crystallinity you have to separate the background from the peaks and compare the areas of both. this is only valid if both the crystalline and amorphous phase have the same scattering factors/densities. if this is not the case you may apply the internal standard method where you add certain amounts of a very high grystalline material and generate a calibration curve..
Looking at your data-
the size will just be the reciprocal of the full-width or integral breadth in units of d (or 1/d) i.e. D= 1/FW(d) . This is the Scherrer equation mentioned above. You can see from your data that this value varies by a lot for data you have as the same phase. It could be you have the phase identification wrong, general errors in your data or the size of the phases is different in different crystallographic directions. Some programs may use the shape of the peak, e.g. how close to Gaussian or Lorentzian it is, but I don't think your program does this.
The Scherrer equation will only work if the sample has no strain present, but its not clear from your data whether there is or not.
d(ang) is not related to crystal size, since Scherrer assume broadening is independent of the d-spacing (d-ang). Although, to convert the FW in 2theta to FW in d does use the d-spacing- so indirectly related.
More on peak profile analysis here: https://www.researchgate.net/publication/301488178_THE_USE_OF_DIFFRACTION_PEAK_PROFILE_ANALYSIS_IN_STUDYING_THE_PLASTIC_DEFORMATION_OF_METALS
Sorry not sure about crystallinity
Thesis THE USE OF DIFFRACTION PEAK PROFILE ANALYSIS IN STUDYING THE...
First u must take a standard reference material (SRM) to subtract the instrument broadening from ur data. But if u know the instrument configuration than better use software with FPA such as Topas, BGMN, Autoquant or PDXL.
It's better refine the whole pattern because there an anisotropy size broadeniung within ur data.
I think this link can help
http://www.instanano.com/characterization/theoretical/xrd-size-calculation/
The calculation done by the link provided by Dheeraj Kuma does not mention subtracting instrumental broadening. It instructs the user to simply enter the measured FWHM. THAT IS VERY BAD! Instrumental broadening must be subtracted from the experimental FWHM!
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