Braggs Law for Finite Size Crystallites

The additional beam path between consecutive lattice planes at the angle 0 + s is  

The phase difference between the top and the bottom layer, p is then  

Pecharsky and P. Y. Zavalij, Fundamentals of Powder Diffraction and Structural Characterization of Materials, Kluwer Academic Publishers, Boston, 2003. 

Post (Eds.), Modern Powder Diffraction, Reviews in Mineralogy Volume 20, Mineralogical Society of America, Chantilly VA, 1989. 

King and L. E. Alexander, X-ray Diffraction Procedures, 2nd edn., John Wiley Sons, New York, 1974. 

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