TEM is having a major problem with sample preparation, whereas XRD is relatively easy as far as sample preparation is concerned, I also found a paper in which XRD was a better method as that the TEM.
I can guess that using XRD you can measure the size the crystals from the amplitude of the diffraction peaks. Monocrystals have high peaks, polycrystalline materials have low diffraction peaks. If you know the size of the crystals you can approximate the dislocation density in that sample
Dear Raghavendra Darji ,
Valentin Bogatu is in principle right;
dislocation density (dd) is calculated via XRD by dd =1/D2 *) with D being the crystallite size D, which is calculated via the ´Scherrer equation' or Williamson-Hall expression;
please see for example the answers to previous similar questions:
https://www.researchgate.net/post/What_is_the_best_method_to_measure_dislocation_density
https://www.researchgate.net/post/How_can_i_calculate_dislocations_density_from_the_XRD_patterns2
especially the paper given there as attachment by A. El-Denglawey (see answer #10)
By the way: D is derived from from the peak width(s), but not from the peak height(s), as mentioned above...
*) Williamson-Smallman relation
Best regards
G. M.
Dear Raghavendra Darji
I think these papers will be helpful for you
Hi Raghavendra Darji, I agreed with Valentin Bogatu and Gerhard Martens . The crystallite size of the sample can be determined from the broadening of the XRD peaks. Mathematically, the dislocation density (δ) can be calculated using:
δ =1/D2 where D is the crystallite size. The unit is nm–2.
Good luck.
Hi Raghavendra Darji, I agreed with Lee. Firtsly you have to calculate the crystallite size from the highly intensed park with proper broadness. Afterwards, you have to calculate the dislocations in nm^-2 by given expression Dr. Lee.
Good luck for you.
Dear Steven Van Petegem ,
you are completely right;
each simple formula has is limitations.
The Williamson-Smallman relation has to be regarded as a very rough estimate.
Already the starting point (Scherrer equation) with the shape factor will lead to a very rough estimate of D and further more the D has a distribution, which is not at all considered here. In addition residual stress is not considered too...
But thanks for the literature.
Best regards
G.M.
Article Investigation of structural, morphological and optical chara...
Raghavendra Darji , kindly refer to the XRD section of the following article:
Article Effect of Cu-N co-doping on the dielectric properties of ZnO...
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