在Mg-Co-Ga系统中,拉维斯相的新三元衍生在Mg-Co-Ga系统中
Nazar Pavlyuk1, Grygoriy Dmytriv1, Volodymyr Pavlyuk1
1Department of Inorganic Chemistry, Ivan Franko National University of Lviv, Kyryla and Mefodiya str. 6, 79005 Lviv, Ukraine.
概括
对Mg-Co-Ga相的晶体结构分析揭示了Laves相,包括六角MgCoGa和扭曲的变体. 三角 Mg$_{0.49}$$ CoGa$_{0.15}$ 阶段表现出两个子细胞的显著障碍.
科学领域:
- 材料科学 材料科学 材料科学
- 晶体学 晶体学是指结晶学.
- 固态化学 固态化学
背景情况:
- Mg-Co-Ga 系统之所以有趣,是因为它有可能形成金属间化合物.
- 岩相是具有多种结构和性质的金属间化合物的重要类别.
研究的目的:
- 为了确定MgCoGa,Mg_{0.74}$CoGa_{0.52}$,Mg_{0.49}$CoGa_{0.15}$相的晶体结构.
- 研究Mg-Co-Ga系统中的结构关系和类型.
主要方法:
- 用单晶X射线衍射分析了晶体结构.
- 结晶学数据被收集并改进为调查的阶段.
主要成果:
- 六边形的MgCoGa阶段采用MgZn$_{2}$结构类型,具有失调.
- 形 Mg$_{0.74}$CoGa$_{0.52}$ 阶段代表了 MgZn$_{2}$ 和 URe$_{2}$ 类型的扭曲变体.
- 三角 Mg$_{0.49}$$ CoGa$_{0.15}$ 阶段显示出相当大的疾病,其特征是有两个亚细胞 (A 和 B) 在 9:1 的比例,其中亚细胞 A 与 MgZn$_{2}$ 类型相关.
结论:
- Mg-Co-Ga 系统形成了具有不同结构特征的拉维斯相.
- 结构关系可以使用组-子组转换来描述,例如Bärnighausen形式主义.
- 在某些阶段存在混乱,如Mg$_{0.49}$$CoGa_{0.15}$,突出了复杂的原子安排.
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