可光开关的分子内穿越空间磁相互作用
Jiaobing Wang1, Lili Hou, Wesley R Browne
1Centre for Systems Chemistry, Stratingh Institute for Chemistry, and Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
Journal of the American Chemical Society
|May 6, 2011
概括
可光开关的基能使两个TEMPO旋转中心之间实现可调节的相互作用. 这种分子系统展示了可控的合,在暴露于光线时从非合到强合状态的切换.
科学领域:
- 分子旋转化学 分子旋转化学
- 摄影化学的使用.
- 超分子化学 超分子化学
背景情况:
- 电子磁共振 (EPR) 光谱是一种强大的工具,用于探测电子环境和磁共振物种的相互作用.
- 可光切换的分子提供了对分子结构和性质的动态控制.
- 调整旋转相互作用对于开发先进的分子材料和传感器至关重要.
研究的目的:
- 为了研究一个过度拥挤的烯的光诱导的切换.
- 描述两个共价连接的TEMPO旋转中心之间的相互作用所产生的变化.
- 为了评估旋转中心对光交换性能的影响.
主要方法:
- 一个分子结构的合成,其中有两个TEMPO旋转中心,由可光开关的过度拥挤的基连接在一起.
- 电子偏磁共振 (EPR) 谱学用于监测自旋合.
- 紫外线-Vis光谱检测证实了基的光交换.
主要成果:
- 基的转态,与TEMPO中心相隔约22 Å,表现出非合的自旋行为 (三线EPR频谱).
- 光异构化到cis状态,将分离减少到~7 Å,诱导强烈的旋转合 (五线EPR频谱).
- 烯的光交换效率仍然很高,不受附加的TEMPO单元的影响.
结论:
- 这项研究展示了一种可光切换的分子系统,光控制着两个自旋中心之间的相互作用.
- 这为光门分子磁力和基于旋转的通信提供了一个平台.
- 光开关的强大性能凸显了其作为复杂分子架构中可靠的切换单元的潜力.
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