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The rate of the deposition reaction increases at higher temperature and the crystallites grow faster resulting in a larger size. Variation of the average crystallite size of PbSe thin films with the deposition temperature.

Effect of crystallite size on lattice strain and crystal structure has been studied using Rietveld refinement and Williamson-Hall plot, respectively. The structural lattice parameters decrease with increasing crystallite size. However, lattice strain increases with increasing crystallite-size.As a general rule, the peaks in the XRD will broaden as crystallite size decreases. As Matteo Leoni describes, the intensity depends on the X-ray flux and the quantity of crystalline materia.

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Article Particle size effects on structural and optical properties o...

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