在二金属酸盐中通过框架灵活性进行热膨胀匹配
Andrew L Goodwin1, Brendan J Kennedy, Cameron J Kepert
1Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK.
Journal of the American Chemical Society
|April 24, 2009
概括
灵活的金属有机框架表现出可调节的热膨胀. 这项研究表明,框架灵活性如何与共结晶组件的热膨胀相匹配,从而最大限度地减少复合材料中的热应力.
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.
- 化学 化学 化学
背景情况:
- 了解热膨胀对于设计稳定的多元组件材料至关重要.
- 同结构性二金属酸盐为研究客宿主相互作用及其对材料性能的影响提供了一个平台.
- 不同类型的热膨胀,包括负热膨胀,在材料设计中提出了独特的挑战和机遇.
研究的目的:
- 为了研究同结构二金属酸盐的热膨胀特性.
- 为了比较一个无客体框架与其同晶体模拟的热行为.
- 探索灵活框架的潜力,以减轻多元组件组件中的热应变.
主要方法:
- 可变温度的单晶X射线衍射.
- 可变温度粉末的X射线衍射.
- 对主体框架和客体阶段的热膨胀系数的分析.
主要成果:
- 没有客的Zn[Au(CN) ((2))))) 框架显示了显著的异性热带正和负热膨胀.
- 同晶体的类似物,Zn[Ag(CN)(2)](2) x xAgCN,显示出更温和的热膨胀.
- 同晶体中Zn[M(CN) (((2))) 主体框架的热膨胀与晶体AgCN组件的热膨胀相匹配.
结论:
- 高度灵活的框架材料具有与附着或联合结晶相的热膨胀性相匹配的一般能力.
- 这种匹配行为表明了在多元组件材料组件中消除热应变的策略.
- 这些发现为设计具有增强热稳定性和性能的先进材料提供了洞察力.
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