Abstract
Systematic selection of reflections, e.g.h ≡ 0 (mod 2), corresponds to a superposition of a structure. If the reflections selected exhibit special extinctions or a higher Laue-symmetry than the whole diffraction pattern, the original structure (S) includes partial symmetry operations and can be described by a mixed group (Mischgruppe) with its space group GS as the kernel (Kern). Possible representatives of the hull (Schale) can be derived from the space group GSPS of the superposed structure (SPS) by decomposing GSPS into a union of the cosets of its subgroup G0SPS which is obtained as the product of the translation group TSPS and GS
© 2015 Oldenbourg Wissenschaftsverlag GmbH, Rosenheimer Str. 145, 81671 München