铁交叉复合体中的双向光交换性:对称性破坏和溶剂效应
Raúl Díaz-Torres1, Guillaume Chastanet2, Eric Collet3
1Thammasat University Research Unit in Multifunctional Crystalline Materials and Applications (TU-MCMA), Faculty of Science and Technology, Thammasat University Pathum Thani 12121 Thailand.
Chemical science
|July 7, 2023
概括
溶剂影响在铁 (III) 材料中的旋转交叉器 (SCO). 观察到双向光交换性和从高旋转/低旋转状态的对称性破坏,揭示了隐藏的状态.
科学领域:
- 材料科学 材料科学 材料科学
- 无机化学 无机化学
- 物理化学 物理化学
背景情况:
- 旋转交叉 (SCO) 是一种现象,其中过渡金属复合体在低旋转 (LS) 和高旋转 (HS) 状态之间切换.
- 溶剂分子可以影响SCO材料中的SCO行为和相变.
- 了解溶剂效应对于设计功能性SCO材料至关重要.
研究的目的:
- 为了研究溶剂对铁 (III) 复合物的旋转交叉 (SCO) 行为的影响.
- 探索SCO溶解物中光诱导的相变和光交换性.
- 阐明溶剂,旋转状态排序和对称性破坏之间的关系.
主要方法:
- 两种铁 (III) SCO酸盐的合成和表征:[Fe (qsal-I) ]2NO3·2ROH (R = Me, 1; R = Et, 2). 铁 (III) SCO酸盐的合成和表征:[Fe (qsal-I) ]2NO3·2ROH (R = Me, 1; R = Et, 2). 铁 (III) SCO酸盐的合成和表征:[Fe (qsal-I) ]2NO3·2ROH (R = Me, 1; R = Et, 2).
- 可变温度磁感应度测量以研究SCO行为.
- LIESST (光诱导激发的旋转状态捕获) 和反向LIESST实验.
- 在10K处进行光晶体学研究,辐射波长各不相同 (980nm和660nm).
主要成果:
- 溶解物1 (MeOH) 呈现突然的SCO,在210K时发生了破坏对称性的相位过渡 ([HS]到[HS-LS]状态).
- 溶解物2 (EtOH) 显示了逐渐的SCO,在T1/2 = 250 K时完成了旋转过渡.
- 索尔维特1显示LIESST和反向LIESST,表示一个隐藏的[LS]状态.
- 溶剂1上的光结晶学揭示了从[HS-LS]状态的双向光诱导相位过渡 (到[HS]或[LS]相位).
结论:
- 溶剂在确定SCO行为 (突然与逐渐) 和过渡温度方面发挥着关键作用.
- 在酸盐1中的[HS-LS]状态允许在高对称性[HS]和[LS]相之间进行光诱导的切换.
- 这项研究展示了铁 (III) SCO材料中的[HS-LS]状态的双向光交换性和对称性破坏的第一个例子.
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