DYNAMICAL X-RAY-DIFFRACTION FROM AN ICOSAHEDRAL QUASI-CRYSTAL

We present direct evidence of dynamical diffraction of x rays from a q uasicrystal. High-resolution x-ray-diffraction measurements of the Al- Pd-Mn face-centered icosahedral quasicrystal were performed, revealing a mosaic full width at half maximum of less than 0.001-degrees. In a second experiment, the anomalous transmission of x rays (the Borrmann effect) was observed. These measurements show that nearly perfect quas icrystals may be grown to centimeter-size dimensions allowing x-ray te chniques based upon dynamical diffraction to be brought to bear on the analysis of icosahedral structures.