Peak Intensity:
If you seen an increase in the relative peak intensity, for instance (111) has higher intensity than (200) and in the another samples is vice versa, this is related to the variations in morphology. But you don't see this, then there are several reasons for that, you can find them in the following article:
Article Diffraction Line Profiles from Polydisperse Crystalline Systems
Peak Width:
This might be due to effect of lattice strain: No Strain: Symmetric peaks, Non-uniform strain: Peak broadening
Based on the Scherrer equation , the peak width can be related to the crystal sizes, if you have bigger crystal sizes, you might have less broaden peak. But this is really an estimate and is often used in conjunction with microscopies (SEM/TEM).
Peak intensity: crystal structure, elements, occupations, substitutions, thermal vibrations, diffractometer geometry, variable or fixed apertures, x-radiation, homogeneity of the sample, texture...
Peak width: diffractometer geometry, diffractometer and detector setup, calibration, homogeneity of the sample, x-radiation, defect density (imperfectness of lattice and structure, polymorphism, amorphisation...)
It is really a basic question but not easy to answer entirely...
Peak Intensity:
If you seen an increase in the relative peak intensity, for instance (111) has higher intensity than (200) and in the another samples is vice versa, this is related to the variations in morphology. But you don't see this, then there are several reasons for that, you can find them in the following article:
Article Diffraction Line Profiles from Polydisperse Crystalline Systems
Peak Width:
This might be due to effect of lattice strain: No Strain: Symmetric peaks, Non-uniform strain: Peak broadening
Based on the Scherrer equation , the peak width can be related to the crystal sizes, if you have bigger crystal sizes, you might have less broaden peak. But this is really an estimate and is often used in conjunction with microscopies (SEM/TEM).
@ M. Shahami: I don't think that the shape is primarily the reason for a higher or lower intensity of an interference hkl of lattice plane (hkl). It only tells you that in case of powder diffraction there are more of (hkl) in "reflection" condition. This can be triggered by the shape but it does not have to. In metals it is mainly the reorganisation caused by plastic deformations. Crystals simply perform a collective rotate. They don't have to but might change also their shape. More complicated it becomes in case of inherited textures during phase transformations.
Peak broadening: our trivial models seem to explain everything but physically it is more complex than it appears. Meaning and limitations of the Scherrer equation or W-H plots have been discussed here at RG many times. I think, the really experts already gave up and do not spend their time for an obviously never ending discussion about the same. Therefore, I would recommend to enter Scherrer equation in the search field... you will be amazed how much time you can save and how often this topic has been discussed already...
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