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通过控制灵活性直接观察金属有机框架中的调节基旋状态

Xiaofeng Chen^1,2, Haomiao Xie², Emmaline R Lorenzo²

¹School of Environmental and Geographical Sciences, Shanghai Normal University, Shanghai 200234, China.

Journal of the American Chemical Society

|February 7, 2022

概括

灵活的金属有机框架可以稳定有机基. 这项研究表明,NU-910 MOF可以在分离的有机基和基二元之间切换,控制固体材料中的自旋状态.

科学领域:

材料科学
化学学
固态物理

背景情况:

有机基具有可切换的自旋状态和动态电子特性,但它们在固体材料中的聚合具有挑战性.
由于其可调节的结构,金属有机框架 (MOF) 为稳定有机基提供了一个有希望的方法.
灵活的MOF对于控制激进行为特别有趣.

研究的目的:

构建一个灵活的,氧化还原活性MOF来固定和控制有机基.
在MOF中研究分离的有机基和基 π-二元之间的旋转状态的调制.
展示柔性MOF在固态激进旋转控制中的潜力.

主要方法:

使用柔性四碳酸连接剂合成一种新的Zr6-MOF,NU-910.
溶剂交换以诱导结构收缩和控制连接器距离.
紫外线照射产生有机基物种.
可变温度单晶X射线衍射和电子磁共振光谱观察旋转状态的切换.
紫外-对-红外光谱和DFT计算以确认基质π-二次体的形成.

主要成果:

一个灵活的MOF与scu拓学的NU-910已成功合成.
从DMF到的溶剂交换导致了NU-910的显著结构收缩.
紫外线辐射在链接器上产生有机基物种.
观察到隔离基与磁性静态基之间的温度诱导切换.
证实了基离子π-二极体的形成.

结论:

灵活的MOF可以有效地隔离和稳定有机基.
在MOF的结构灵活性允许激进旋转状态的调节.
在固体阶段控制激进动态的平台.
这种方法对开发具有可切换电子和磁性特性的先进材料有影响.

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