The invariance principle of Ambarsumian is applied to the solution of X‐ray diffraction problem in single crystals in the symmetric Bragg case. A quadratic equation with respect to the reflection coefficient ϱ is obtained for a semi‐infinite crystal. Evident expressions for the reflection coefficient ϱn and transmission coefficient Qn are found by establishing relations between the solution of the diffraction problem in the crystal with a finite number n of reflecting planes and that of the diffraction problem in a semi‐infinite one. The formulas obtained may be applied to any periodically layered medium.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.