Department of Chemistry, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, UK.
Phys Chem Chem Phys. 2013 Jun 14;15(22):8672-7. doi: 10.1039/c2cp43732e.
A study of the magnetic and structural properties of the double perovskite Ba2GdMoO6 has been performed. The crystal structure distorts from the ideal cubic (Fm3m) structure to the tetragonal space group I4/m at 220 K, before undergoing a second distortion to a triclinic system (I1) at 80 K. The phase transition to triclinic symmetry is also evident in magnetic susceptibility measurements. The variable temperature synchrotron powder X-ray diffraction results reveal that Ba2GdMoO6 is ferroelastic, with the onset of ferroelastic domain formation occurring at the cubic-tetragonal phase transition. A number of Rietveld refinement techniques for modelling diffuse scattering from ferroelastic domain boundaries have been explored.
对双钙钛矿 Ba2GdMoO6 的磁性和结构性质进行了研究。晶体结构在 220 K 时从理想的立方（Fm3m）结构扭曲到四方空间群 I4/m，然后在 80 K 时再次扭曲为三斜晶系（I1）。磁导率测量也表明发生了向三斜对称相的转变。变温同步加速器粉末 X 射线衍射结果表明 Ba2GdMoO6 是铁弹性的，铁弹性畴形成始于立方-四方相转变。探索了多种用于模拟铁弹性畴界漫散射的 Rietveld 精修技术。
