A Dynamical Diffraction Theory of X-rays for a Largely Distorted Crystal II. Application of the Green’s Function Method

The solution of the fundamental equation of the wave field for a largely distorted crystal is expressed, using the Green’s function method. A Green’s function is introduced in a tensor form for the Maxwell’s equation for the electric field vector. Using Stratton’s theorem, the wave filed inside the crystal is expressed as an integral using the Green’s function on the crystal surface. Furthermore, the Green’s function is expressed as a sum of two functions referred as a forward transfer function and a backward one, the former of which mainly contributes the above surface integral. From this result, in the case that all significant wave components of the transmitted and other diffracted waves emerge from the exit crystal surface as in the Laue case diffraction, the wave field inside the crystal for an arbitrary incident wave is decided directly as an integral over the entrance crystal surface with the forward transfer Green’s function