Abstract: | The asymmetrical Bragg case of X-ray diffraction on a thick real crystal is theoretically investigated on a layer model containing dynamically diffracting mosaic blocks. By means of this theory the experimental dependence of the integrated reflectivity Ri on the asymmetry angle α deviation from the kinematical formula may be understood as a result of extinction- and absorption processes inside the mosaic crystal. Thus the remarkably thick surface layers or surface protuberances assumed by Mathieson and in previous papers for the interpretation of the experimental Ri(α) become needless or they are considerably thinner. respectively, indeed. – On the base of the represented theory the determination of special (model-dependent) characteristics of the dislocation network is possible via absolute Ri(α)-measuring values. |