摘要
A novel formulation of X-ray diffraction and refraction is derived from the dynamical theory of X-ray diffraction. All the expressions of the dispersion relation, wave field amplitudesand reflectivities are given in analytic forms which are valid for the whole angular range of thesymmetric diffraction geometry. In addition to putting Fresnel’s reflectivity and Darwin’s curveinto a unified scheme, this framework provides a precise physical picture of diffraction fromperiodic media. © 1993 IOP Publishing Ltd.