多稳定旋转交叉分子材料的非常长寿命光生成高旋转相
Teresa Delgado1, Antoine Tissot2, Laure Guénée3
1Département de Chimie Physique , Université de Genève , 1211 Genève , Switzerland.
Journal of the American Chemical Society
|September 15, 2018
概括
旋转交叉铁复合体在光激发的旋转状态陷后表现出较长的放松时间. 由于丁链的重新排列,该化合物[Fe(n-Bu-im) 3(tren) ](PF6) 2在80 K时显著放松.
科学领域:
- 材料科学
- 固态化学
- 物理化学
背景情况:
- 旋转交叉 (SCO) 化合物表现出低旋转和高旋转状态之间的切换.
- 光诱发激发状态捕获 (LIESST) 是一种用于诱导SCO的现象.
- 了解放松动态对于SCO材料的应用至关重要.
研究的目的:
- 为了研究SCO化合物的异常长的放松时间[Fe{n-Bu}im}3{tren}}{PF6}2.
- 阐明在不同温度下 LIESST 后影响放松行为的因素.
- 将结构变化与观察到的放松动态相关联.
主要方法:
- 光学吸收光谱检测旋转状态.
- 磁力测量用于量化磁性和自旋状态.
- 使用同步射线的X射线衍射来确定晶体结构.
- 可变温度研究 (10K到80K) 观察温度依赖的效应.
主要成果:
- 在 LIESST 后,SCO 化合物 [Fe ((n-Bu-im) 3 ((tren) ] ((PF6) 2) 在 80 K 的放松时间为 20 小时,远远长于 10 K 的放松时间.
- 发现休息时间高度依赖温度,急剧增加至70K以上.
- 在较高温度下放松时,X射线衍射显示了联体中的丁链的重新排列.
结论:
- 在80K的异常长的放松时间归因于连接体结构中的丁链的重新排列.
- 这种分子重组可能会影响能量格局, 阻碍回归基旋状态.
- 这些发现突显了连接物灵活性和温度对SCO放松动态的重要性,为设计新的SCO材料提供了洞察力.
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