双钙钛矿Sr2Mn1-xGaxMoO6（x=0．0～1．0）化合物的制备及其结构的研究

采用固相反应法制备了双钙钛矿Sr2Mn1-xGaxMoO6（x=0．0～1．0）掺杂化合物。室温下的高分辨率X射线衍射分析表明，Sr2MnMoO6具有单斜晶体结构，空间群为P21／n。Ga的掺杂没有改变化合物的晶体结构，但衍射峰整体向高角度漂移。结构精修分析表明，Sr2Mn1-xGaxMoO6样品的晶胞体积随Ga含量的增加而逐渐减小；B／B’位离子占位有序度伴随Ga的掺入而逐渐降低；此外，Ga的引入导致〈B—O〉键长的缩短，〈B’-O〉键长的伸长。

Preparation and Structural Analysis of Double-Perovskite Compound Sr2Mn1-xGaxMoO6(x=0.0～1.0)

The double-perovskite Sr2Mn1-xGaxMoO6（x = 0.0 - 1.0） compounds are prepared by solid state method. A room temperature a- nalysis of high-resolution X-ray powder diffraction patterns indicates that the structure of Sr2 MnMoO6 compound crystallize,which is in the monoclinic space group P2 t/n, does not change with the Ga doping, but the whole X-ray powder diffraction profiles shift to higher degree. The strnctural refinement has shown that the unit cell volume of Sr2Mn1-xGaxMoO6 compounds decrease with the Ga concentration; B/B＇ site cationic ordering decreases with Ga doping; the introduction of Ga leads to extension of bond 〈 B - O 〉 and shrinkage of bond 〈 B＇ -O 〉.