X-ray diffraction from an atomic plane

Reflection and transmission coefficients of X-rays by a single atomic plane are obtained in the general case where the plane consists of any two-dimensional Bravais lattice and the incident and exit X-ray beams take any direction with respect to the plane. A formula obtained for the coefficients is written in a simple form, different from that obtained by Durbin [Acta Cryst. (1995), A51, 258-268]. This makes it possible to extend Darwin's dynamical theory of X-ray diffraction to general geometries which include the cases of asymmetric skew reflection and noncoplanar multibeam diffraction.