The crystal structures and physical properties of the solid solution compound Ba<sub>5</sub>Y<sub>8-x</sub>Mn<sub>4</sub>O<sub>21-1.5x</sub>(x = 0,1) |
| |
引用本文: | 高庆庆,李静波,宋士佳,饶光辉,骆军,刘广耀,梁敬魁.The crystal structures and physical properties of the solid solution compound Ba5Y8-xMn4O21-1.5x(x = 0,1)[J].中国物理 B,2012(6):368-373. |
| |
作者姓名: | 高庆庆 李静波 宋士佳 饶光辉 骆军 刘广耀 梁敬魁 |
| |
基金项目: | Project supported by the National Natural Science Foundation of China (Grant Nos. 50872148 and 51072225);the National Basic Research Program of China (Grant No. 2007CB925003) |
| |
摘 要: | New oxometallides with the formula Ba5Y8 xMn4O21 1.5x(x = 0,1) are prepared through an atmospherecontrolled solid-state reaction.Two single-phase samples with Ba/Y/Mn atomic ratios 5/8/4(Y8) and 5/7/4(Y7) are obtained.The crystal structures and the physical properties of the compounds are investigated by X-ray powder diffraction,magnetization,conductivity,and dielectricity measurements.The Ba5Y8 xMn4O21 1.5x compound is demonstrated to be a Y-deficient solid solution.The solid solution compound Ba5Y8 xMn4O21 1.5x crystallizes into tetragonal symmetry with the space group I4/m.Detailed structure analysis by Rietveld refinement of the X-ray powder diffraction data reveals that the Y vacancies occur preferentially at the Y(2) site.Thermal magnetization measurements indicate the presence of antiferromagnetic interaction between Mn ions in the compounds,and temperature-dependent resistivity measurements show that insulator-semiconductor transitions occur around 175 K and 170 K for the Y8 and Y7 samples,respectively.Strong frequency dependences of the dielectric constant are observed above ~175 K for the two compounds.
|
关 键 词: | Ba5Y8 xMn4O21 1.5x X-ray powder diffraction crystal structure conductivity |
本文献已被 维普 等数据库收录! |
|