编程孔形状固定在柔软的多孔分子晶体中 - 导航相间转换景观
Alan C Eaby1, Leigh Loots1, Jeanice L Basson1
1Department of Chemistry and Polymer Science, University of Stellenbosch, Private Bag X1, Matieland, 7602, Stellenbosch, South Africa.
Angewandte Chemie (International ed. in English)
|June 3, 2023
概括
在p-tert-butylcalix[4]arene (TBC4) 的软多孔晶体中观察到孔形状固定效应. 较小的TBC4晶体表现出固定的多孔结构,不同于较大的晶体,显示出粒子大小依赖的现象.
科学领域:
- 材料化学 材料化学
- 超分子化学 超分子化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 在柔软的多孔晶体中,孔形状固定效应 (PSFE) 仍未得到充分研究.
- 动态范德瓦尔斯固体为结构操纵提供了独特的可能性.
研究的目的:
- 在原型的动态范德瓦尔斯固体p-tert-butylcalix[4]arene (TBC4) 中调查和报告PSFE.
- 了解控制TBC4.4中客体诱导相变的分子层次机制.
主要方法:
- 变压 (VP) 单晶和粉末X射线衍射. 变压 (VP) 单晶和粉末X射线衍射.
- VP差异扫描热量测量. 这是一个非常好的方法.
- 卷度吸附分析和减弱的总反射率 里埃变换红外光谱学.
主要成果:
- 在TBC4中使用CO2压力和温度编程了两个不同的多孔形状固定阶段.
- 发现相间转换取决于粒子大小:较小的晶体表现出固定的转移稳定相,而较大的晶体表现出可逆转换.
- 为TBC4建立了一个全面的相间转换方案.
结论:
- 这项研究提供了PSFE在多孔分子晶体中的第一个例子.
- 这些发现突出了通过外部刺激和粒子大小控制多孔晶体结构的潜力.
- 已建立的相间转换方案允许对TBC4的结构景观进行可预测的导航.
相关概念视频
Phase Transitions: Melting and Freezing
12.5K
Heating a crystalline solid increases the average energy of its atoms, molecules, or ions, and the solid gets hotter. At some point, the added energy becomes large enough to partially overcome the forces holding the molecules or ions of the solid in their fixed positions, and the solid begins the process of transitioning to the liquid state or melting. At this point, the temperature of the solid stops rising, despite the continual input of heat, and it remains constant until all of the solid is...
12.5K
Crystal Growth: Principles of Crystallization
2.2K
Crystallization is a phase transformation process in which crystals are precipitated from a supersaturated solution or formed from other sources. During crystallization, atoms or molecules arrange themselves into a well-defined, rigid crystal lattice to minimize energy.
Initiating crystallization involves manipulating the concentration of the solute and the temperature of the solution. Since crystal growth occurs when the ratio of concentration and solubility of the solute in the solvent...
Initiating crystallization involves manipulating the concentration of the solute and the temperature of the solution. Since crystal growth occurs when the ratio of concentration and solubility of the solute in the solvent...
2.2K
Polymer Classification: Crystallinity
2.9K
Unlike ionic or small covalent molecules, polymers do not form crystalline solids due to the diffusion limitations of their long-chain structures. However, polymers contain microscopic crystalline domains separated by amorphous domains.
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
2.9K


