超越 π-π 堆叠:了解晶体树脂中的反对称破裂
Yiran Wang1, Matthew L Nisbet1, Kendall R Kamp1
1Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States.
Journal of the American Chemical Society
|July 24, 2023
概括
研究人员通过控制分子堆叠来探索如何创建非中心对称 (NCS) 材料. 他们发现铜 (Cu) 赛马体之间的非平行堆叠相互作用阻止了反转中心,使NCS晶体形成.
科学领域:
- 固态化学和材料科学
- 晶体学
- 协调化学
背景情况:
- 设计非中心对称 (NCS) 固态材料是具有挑战性的,因为racemic建筑单元的复杂性.
- 之前的工作确定了NCS结构在[Cu(H2O) ((bpy) ]2[MF6]2·2H2O化合物中,在NCS空间组Pna21中结晶.
- 对于具有特定性质的材料来说,了解如何打破反向对称性至关重要.
研究的目的:
- 用二甲基-双胺配体合成和表征新的铜复合物.
- 研究影响中心对称 (CS) 与非中心对称 (NCS) 晶体结构的结构因素.
- 开发一个用于控制NCS材料的反向对称性的框架.
主要方法:
- 合成了五种新的化学化合物: [Cu(H2O) ((dmbpy) 2[MF6]2·xH2O.
- 单晶X射线衍射以确定晶体结构.
- 使用七种结构描述物的分子间相互作用分析.
主要成果:
- 五种新的化合物结晶在中心对称 (CS) 空间组中,与之前报告的NCS类型不同.
- CS结构的特征是相邻的铜 (Cu) 赛马体之间的平行异体 π-π 堆叠相互作用.
- NCS结构具有非平行的异体 π-π 堆叠,这排除了反转中心的形成.
结论:
- 甲基替代联体的几何结构,特别是dmbpy,有利于平行π-π堆叠,导致CS结构.
- 引入非平行堆叠相互作用是抑制反转中心和实现NCS赛马的关键策略.
- 通过控制分子间堆叠来设计NCS材料的概念框架.
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