My multi phase system contains Anatase .brookite and rutile so peaks are overlapping in that case how I can use scherrer equation to get crystallite size?
Is that I have to deconvulate the first intense peak for different phases than intensisty ratio and all how it will work ?
Please give suggestion..
You need to deconvolute the entire diffractogram in order to get each phase separately. As you already know from other question you were asking for, this is only possible using certain assumptions (which are not rarely very subjective) and therefore the resulting phase contributions will be different from assumption to assumption. This has impacts on the used Hall plot which enables the derivation of the size of the coherently scattering volumes (lets call them grains). If phases have enough separate peaks you have good chances to get reliable numbers. Not absolutely correct but at least relatively. For rutile and anatase this is acceptable. The peaks do not match that much. Very important is also the phase fraction. If you have very different phase fractions (better: the intensity of the peaks are remarkably different) the extraction of the reflection widths (FWHM) is highly erroneous. For phases with strong scattering you can still get results for a phase fraction of only a few percents. On the other hand, also the symmetry is important factor since low symmetric phases have numerous and statistically less intense interferences.
In your case the brookite is dominates the signal and the width of the peaks only tell me that it has a very small grain size (Lorentzian shape of the interferences) and the single reflections are no more detectable. Good luck to make there a reliable analysis. The residual intensities of rutile and anatase nearly disappear in the background. I would recommend to reduce the noise in the background in order to get them in a better quality. On the other hand, if you only want to know roughly how big is the difference it is perhaps OK. But again: don't trust the absolute values that much since there are several other parameters influencing the final number, e.g. how big is the instrumental impact.
You need to deconvolute the entire diffractogram in order to get each phase separately. As you already know from other question you were asking for, this is only possible using certain assumptions (which are not rarely very subjective) and therefore the resulting phase contributions will be different from assumption to assumption. This has impacts on the used Hall plot which enables the derivation of the size of the coherently scattering volumes (lets call them grains). If phases have enough separate peaks you have good chances to get reliable numbers. Not absolutely correct but at least relatively. For rutile and anatase this is acceptable. The peaks do not match that much. Very important is also the phase fraction. If you have very different phase fractions (better: the intensity of the peaks are remarkably different) the extraction of the reflection widths (FWHM) is highly erroneous. For phases with strong scattering you can still get results for a phase fraction of only a few percents. On the other hand, also the symmetry is important factor since low symmetric phases have numerous and statistically less intense interferences.
In your case the brookite is dominates the signal and the width of the peaks only tell me that it has a very small grain size (Lorentzian shape of the interferences) and the single reflections are no more detectable. Good luck to make there a reliable analysis. The residual intensities of rutile and anatase nearly disappear in the background. I would recommend to reduce the noise in the background in order to get them in a better quality. On the other hand, if you only want to know roughly how big is the difference it is perhaps OK. But again: don't trust the absolute values that much since there are several other parameters influencing the final number, e.g. how big is the instrumental impact.
@Kenneth M Towe
Dear Sir,
shape of anatase is spherical, brookite are nanorods and rutile grows from them converting at high temperature either by % change of Brookite and rutile.
@Gertz Nozle but Sir how to deconvolute the entire XRD spectra? which software you used for it
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