聚氧甲酸通过{Mo2O2S2} 协调板块:一个超分子六合体支架的阴离子导向构造和化学结构
Jérôme Marrot1, Marie Anne Pilette, Mohamed Haouas
1Institut Lavoisier de Versailles, UMR 8180, Université de Versailles Saint Quentin, 45 Avenue des Etats-Unis, 78035 Versailles, France.
Journal of the American Chemical Society
|December 14, 2011
概括
这项研究探讨了聚氧甲 (POM) 和-硫集群的组装成六米,四米和二米结构. 酸影响组合,离子对六合体稳定性和灵活性至关重要.
科学领域:
- 超分子化学 超分子化学
- 无机化学 无机化学 有机化学
- 材料科学 材料科学 材料科学
背景情况:
- 聚氧甲酸盐 (POMs) 是多功能无机集群,具有多样化的应用.
- [Mo}2) O}2) S}2) OH}2) 6}2+) 水电离子 (L) 和三电离子[AsW}9) O}33) ]9-) POM是关键的构建块.
- 了解它们的自我组装对于设计新型功能材料至关重要.
研究的目的:
- 为了研究POM和硫单元的自组装到离散架构中.
- 阐明酸盐和离子强度在指导不同超分子结构形成中的作用.
- 描述由此产生的集群的结构,构造和稳定性质.
主要方法:
- 六度,四度和二度集群的合成和结构特征.
- 用X射线结晶学进行详细的结构分析.
- 核磁共振 (NMR) 光谱学 ((183) W, (39) K) 和UV-Vis光谱学用于溶液稳定性研究.
- 密度函数理论 (DFT) 计算用于几何和能量优化.
主要成果:
- 组装了三个不同的架构:一个六合体 (1),一个四合体 (2) 和一个二合体 (3).
- 六美式脚手架 (1) 具有显著的灵活性,具有两种不同的构造 (遮蔽和分阶离).
- 酸,特别是,在稳定六合体和通过宿主-客人相互作用影响其构造方面发挥着关键作用.
结论:
- 基于POM和-硫单元的化学系统允许控制的形成各种超分子结构.
- 酸盐作为必不可少的"粘合剂",调解组装并稳定结构,特别是柔性六合体.
- 这项工作为管理复杂无机集群形成的自我组装原则提供了基本的见解.
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