在二二衍生物的表面进行多态选:发现新的溶剂形式
Ann Maria James1, Nemo McIntosh2, Félix Devaux3
1Institute of Solid State Physics, Graz University of Technology, Petersgasse 16, 8010 Graz, Austria. roland.resel@tugraz.at.
Materials horizons
|July 21, 2023
概括
表面结晶使得发现了四种新的分子材料酸盐,以前通过传统选方法无法获得. 这些通过X射线衍射识别的新型酸盐在环境条件下具有独特的材料特性.
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.
- 超分子化学 超分子化学
背景情况:
- 分子材料的物理性质高度依赖于它们的晶体结构,多态的发现对新应用至关重要.
- 传统的多态选方法往往无法访问各种晶体相,限制了材料性质的探索.
- 表面结晶为控制结晶条件和获取新型多态态提供了一个有前途的途径.
研究的目的:
- 探索表面结晶的潜力,以发现分子材料的新多态.
- 为了研究乙烯糖醇-二二二烯分子的新型溶解物相的形成和表征.
- 通过表面结晶与经典选来比较这些阶段的可访问性.
主要方法:
- 使用表面结晶来诱导新结晶相的形成.
- 使用X射线衍射 (XRD) 确定新发现的相的晶体结构.
- 使用X射线光,拉曼光谱和体积分析进行相位识别和表征.
主要成果:
- 通过表面结晶,成功合成并对目标分子进行了四个新的溶盐相的表征.
- 发现的酸盐中没有一个通过常规的多态选来确定.
- 三种溶酸盐的特征是每个分子含有一个,两个或三个溶剂分子 (二甲),与乙烯糖醇侧链观察到强烈的相互作用.
结论:
- 表面结晶提供了对结晶动力学的精确控制,使得人们能够获得以前无法获得的多种溶酸盐.
- 发现的溶酸盐具有较低的热稳定性,但在环境条件下长时间 (≥2年) 保持稳定.
- 这种方法突出了工程表面环境在扩大分子材料已知的相空间方面的潜力.
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