High-temperature powder synchrotron diffraction studies of synthetic cryolite Na3AlF6

摘要

A high-resolution synchrotron diffraction study of the structures of a synthetic sample of cryolite Na3AlF6 from room temperature to 800degreesC is reported. At room temperature Na3AlF6 is monoclinic and the structure is described in space group P2(1). Heating the sample to 560degreesC results in only minor changes to the structure. A first-order transition from this monoclinic Structure to a high-temperature Cubic structure is observed near 567degreesC. The cubic Fm (3) over barm structure is characterized by disorder of the fluoride atoms. Crown Copyright (C) 2003 Published by Elsevier Inc. All rights reserved. [References: 24]