旋转交叉在阳离子桥式富勒 (Bu4N+) {Co(Ph3P)}2(μ2-Cl-)
Dmitri V Konarev1, Salavat S Khasanov2, Alexander F Shestakov1
1Institute of Problems of Chemical Physics RAS , Chernogolovka, Moscow Region 142432, Russia.
Journal of the American Chemical Society
|December 13, 2016
概括
在-富勒烯复合体中观察到旋转交叉现象. 这种转变涉及到富勒的电荷转移,形成五重奏激发状态.
科学领域:
- 无机化学
- 材料科学
- 超分子化学
背景情况:
- 旋转交叉 (SCO) 是一种现象,其中过渡金属复合物可以在低旋转和高旋转状态之间切换.
- 富勒烯 (C60) 是具有独特电子和结构性质的碳基.
- 阳离子-富勒烯复合物为新型电子和磁性材料提供了潜力.
研究的目的:
- 为了研究新型阳离子-富勒烯复合物的旋转交叉现象.
- 阐明涉及电荷转移的自旋转变的机制.
- 描述复合体的电子和磁性状态.
主要方法:
- 复合物的合成和表征 (Bu4N+) {Co(Ph3P) }2(μ2-Cl-) ((μ2-η2,η2-C60) 2·2C6H14 (1).
- 测量磁性易感性以检测旋转转变.
- 探测电荷转移事件的光谱技术.
主要成果:
- 在150K以上的复合体1中观察旋转交叉现象.
- 该二元体表现出一个三元基态,其中有两个弱合的Co(0) 原子 (S = 1/2).
- 旋转转移伴随着到富勒的电荷转移,形成五重奏激发状态,具有高旋转的Co (I) (S = 1) 和C60•- (S = 1/2).
结论:
- 这项研究证明了由电荷转移驱动的-富勒烯二元体中的旋转交叉.
- 这一发现突显了基于富勒的复合物开发可切换分子材料的潜力.
- 观察到的旋转过渡机制为金属富勒烯系统的电子动态提供了洞察力.
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