可光分解的外部连接体的光诱导旋转变化:分子磁切换的新原理
Steffen Thies1, Hanno Sell, Christian Schütt
1Otto-Diels-Institut für Organische Chemie, Christian-Albrechts-Universität, Otto-Hahn-Platz 4, D-24098 Kiel, Germany.
Journal of the American Chemical Society
|September 6, 2011
概括
研究人员使用光线在单个分子中实现了室温磁性切换. 这种由光驱动的协调诱导的旋转状态切换 (LD-CISSS) 为分子磁性提供了新的可能性.
科学领域:
- 分子磁力学分子磁力学
- 超分子化学 超分子化学
- 摄影化学的使用.
背景情况:
- 旋转交叉材料中的磁位稳定性通常是一种集体固态现象.
- 在溶液中实现分子级磁切换是一个重大挑战.
研究的目的:
- 为了证明光驱动的单个分子在均溶液中的磁性切换.
- 在分子层面研究光驱协调诱导的旋转状态切换 (LD-CISSS) 的机制.
主要方法:
- 使用Ni-氨酸作为一个方形平面平台和阿佐氨酸作为可光分解的轴联体.
- 采用紫外线 (365nm) 和可见光 (455nm) 来诱导亚索皮里丁的跨异体化,改变协调和自旋状态.
- 确定了氨酸/亚索皮里丁复合物的关联常数,并评估了替代剂大小对切换效率的影响.
主要成果:
- 在溶液中的Ni-氨酸复合物中,证明了二磁性 (低旋转,S=0) 和二磁性 (高旋转,S=1) 状态之间的可逆切换.
- 在室温下使用异基替代性亚索皮里丁,实现了对20-68%的偏磁性Ni物种的光诱导,可逆切换.
- 表明,在阿佐皮里丁上更大的替代剂增强了异构体之间的结合常数的差异,提高了切换效率.
结论:
- 溶液中的单个分子可以表现出光驱动的磁性双稳定性.
- LD-CISSS提供了一种新的途径,可以使用光来控制分子磁性.
- 该系统为开发新的分子开关和记忆器件提供了潜力.
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