Observation of X‐Ray Kossel Patterns (“Gitterquelleninterferenzen”) from Quasicrystals

Kossel interferences of CoKα- and NiKα-radiation are observed, using a 30 keV electron beam to excite fluorescence radiation inside a two-dimensional Al 70 Co 15 Ni 15 quasicrystal. The reflections detected allow a determination of lattice parameters and crystal orientation. Furthermore some of the Kossel lines possess a fine structure as is known from periodical crystals. Especially the occurrence of the light-dark contrast is an indicator for a constant phase shift between the primary and diffracted x-rays, and for the dynamical character of the process, respectively