SINGLE-CRYSTAL DIFFRACTION BY SUBMICROMETER SIZED KAOLINITE - OBSERVATION OF BRAGG-REFLECTIONS AND DIFFUSE-SCATTERING

For the first time single crystal diffraction experiments on individua lly mounted kaolinite crystals with volumes of 8 mu m(3) to 0.4 mu m(3 ) are reported. The diffraction patterns prove that no reflections vio lating the C-centering exist, confirming the space group C1 for kaolin ite. Preliminary refinements confirm the structural model of kaolinite in C1. Non-hydrogen atoms could be refined anisotropically and the hy drogen positions could be refined as well. The diffraction patterns sh ow diffuse scattering in streaks along OOl through hkl reflections wit h hk not equal zero, which is caused by stacking faults. The diffracti on pattern of the smallest (0.4 mu m(3)) sample also reveals micro twi nning and diffuse scattering. This sample consists of domains of left and right handed kaolinite.