Incommensurate superlattice reflections have been observed by X-ray diffractometry in K2SeO4 and (NH4)2BeF4. A simple method is proposed based on the ω-scan technique. This is free from systematic errors, and is not affected by the precision of the lattice constant determination. The incommensurate superlattice parameter of K2SeO4 measured using this procedure is in agreement with that measured using neutron scattering. The incommensurate structure of (NH4)2BeF4 is elucidated for the first time by the present method.
ASJC Scopus subject areas
- Physics and Astronomy(all)