The factors affecting the polarization transformations of X-rays in Laue diffraction from crystals with dislocations

The transformations of X-ray polarization with coherent sigma- and pi -comp onents have been studied for the Laue diffraction from LiF crystals with a high dislocation density (10(4)-10(5) mm(-2)). The dependence of the parame ter characterizing the diffraction-induced birefringence and the degree of coherence of the transmitted beam on the squared reciprocal-lattice vector (H-2 = 4sin(2)theta/lambda (2)) is determined. It is shown that the paramet er characterizing the diffraction-induced birefringence in crystals with di slocations is determined by the static Debye-Waller factor (exp(-L)) and th e effective thickness Delta of the crystal. The exponent L increases and th e parameter Delta decreases with the dislocation density. (C) 2001 MAIK "Na uka/Interperiodica".