结构相关的兰化物-的异型热膨胀 (II) 化物协调聚合物
Thomas E Karpiuk1, Daniel B Leznoff1
1Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia V5A 1S6, Canada.
Inorganic chemistry
|December 25, 2023
概括
这项研究合成了新的化协调聚合物,揭示了独特的热膨胀特性. 这些材料具有可调节的负和零热膨胀,这对于先进的材料设计至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 无机化学 无机化学 有机化学
- 固态化学 固态化学
背景情况:
- 协调聚合物根据其结构提供可调节的特性.
- 兰化物和 (II) 化物复合物因其独特的电子和结构特性而引起人们的兴趣.
- 了解热膨胀对于设计各种应用的材料至关重要.
研究的目的:
- 合成和结构性表征新的化协调聚合物.
- 为了研究这些新型化合物的热膨胀行为.
- 为了将观察到的热膨胀特性与材料的结构架构相关联.
主要方法:
- 使用兰化 (LnCl3·xH2O) 和 (II) 化 (Hg (CN)) 合成协调聚合物2).
- 使用X射线衍射技术进行结构性表征.
- 使用温度依赖测量的热膨胀行为的分析.
主要成果:
- 一种3D协调聚合物,[Ce(OH2) [5][Hg(CN) 2Cl]3·2H2O,表现出单轴负热膨胀.
- 基于二维板材的化合物[Ln(OH2) x]2[Hg(CN) ]5Cl6·2H2O,表现出单轴零热膨胀.
- 零热膨胀的方向在二维结构内有所不同,突出了结构灵敏度.
结论:
- 这项研究表明,化协调聚合物的化-的结构框架及其热膨胀特性之间存在明显的关系.
- 不同类型的热膨胀,包括负和零膨胀,可以通过操纵协调聚合物结构来实现.
- 这些发现为设计具有量身定制的热反应的先进材料提供了洞察力.
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