Reinvestigation of the structure of BaCuSi(2)O(6) -- evidence for a phase transition at high temperature.
Superstructure reflections have been observed in the room-temperature X-ray diffraction pattern of BaCuSi(2)O(6), barium copper disilicate. The tetragonal structure has a fourfold unit-cell volume compared with the original structure determined by Finger et al. At T(s) = 610 K BaCuSi(2)O(6) undergoes a structural phase transition upon which the superstructure reflections disappear. The description of the structure in the larger cell removes the crystal-chemical inconsistencies observed for the original structure.
Sparta
Karine M
KM
Institut für Kristallographie, RWTH Aachen, 52056 Aachen, Germany.
Roth
Georg
G