一些空位排序的合金化物佩洛夫斯基特的结构性质
Caleb J Bennett1, Helen E A Brand2, Alexander K L Yuen1
1School of Chemistry, University of Sydney, F11, Sydney, NSW 2006, Australia.
Inorganic chemistry
|February 27, 2024
概括
由于纳六合酸盐 (Na2PtX6·6H2O) 的脱水,由于小纳酸盐的存在,形成空位秩序的矿石. 较大的金属产生稳定的无水六化物,盐表现出温度依赖的结构相变和八面体倾斜.
科学领域:
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
- 材料科学是一种材料科学.
背景情况:
- 六化性金属六金酸盐 (A2PtX6·6H2O) 的脱水对于理解它们的结构转变至关重要.
- 阴离子大小在稳定无水相和影响晶体对称性的作用是研究的一个关键领域.
研究的目的:
- 用现场同步X射线衍射研究Na2PtX6·6H2O (X = Cl, Br) 的脱水过程中的结构变化.
- 探索不同金属酸 (Na,K,Rb,Cs) 对无水六合金结构的形成和稳定性的影响.
- 描述PtX6八面体相位转换和合作倾斜的特征,与温度和阴离子大小相关.
主要方法:
- 在现场可变温度同步射线X射线衍射被用来研究脱水过程.
- 分析了水晶结构,以确定相位过渡和对称性变化.
- 格莱泽倾斜符号被用来描述PtX6八面体的合作倾斜.
主要成果:
- 由于Na2PtX6·6H2O的脱水产生了空位排序的双矿 (Na2PtX6) 由于Na离子很小,导致PtX6八面体倾斜和对称性减少.
- 较大的金属 (K,Rb,Cs) 促进稳定的无水六化物的形成,而这些六化物没有表现出化的倾向.
- 六合金酸盐 (K2PtBr6,K2PtI6) 呈现出从立方体 (Fm3̅m) 到四边形 (P4/mnc) 和最终到单边形 (P21/n) 的温度依赖的相位过渡结构,与增加的PtX6八面体倾斜相关.
结论:
- 金属离子的大小显著影响了六白金酸盐脱水的结构结果.
- PtX6八面体的合作倾斜是推动这些化合物的对称性降低的关键机制.
- 了解这些相位过渡对于设计和利用新型无机材料至关重要.
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