Crystal Size and Lattice Distortion - Separability

Why is it possible to separate crystal size from lattice distortion — Limited crystal size broadens every reflection by the same amount . On the other hand, the higher the order of a reflection is, the higher is the smearing effect caused by lattice distortions. 

Disregarding the crystal size distribution in a polycrystalUne sample, the observed profile of any peak 

After Hobs has properly been extracted (cf. Sect. 2.2.2), the effect of instrumental broadening can be eliminated by numerical deconvolution (see p. 38). If the peaks shall be modeled by analytical functions (Sects. 8.2.5.7-8.2.S.8), the consideration 

In the presented form Eq. (8.13) is only valid, if Hj (s) is, indeed, constant over the whole angular range required for analysis. If this is not the case and numerical deconvolution is aimed at, the standard algorithm may be adapted by consideration of the fact that, in any case, the broadening is a slowly varying function of 20. 

---