连接物修饰产生双阶段的磁性切换在一个 ((二氧化)) 复合体.
Khadanand Kc1, Toby Woods2, Lisa Olshansky1
1Department of Chemistry, Center for Biophysics and Quantitative Biology, Materials Research Laboratory, University of Illinois, Urbana-Champaign, Urbana, Illinois, 61801, USA.
Angewandte Chemie (International ed. in English)
|September 21, 2023
概括
研究人员开发了一种新型的复合物,它具有修改后的连接体,可实现两步磁性切换. 这一突破提供了第三种磁性状态,并为先进的分子开关提供了潜力.
科学领域:
- 协调化学 协调化学
- 材料科学 材料科学 材料科学
- 分子磁力学分子磁力学
背景情况:
- 单核复合体与单二二烯配体在低旋转 (l.s.) 之间表现出对应性分离体 (VT). III (catecholato) 和高旋转 (h.s.) 的情况 同子 (seminquinonato) 的状态.
- 牙联体框架通常支持这些状态,影响VT过渡的温度.
- 在这些系统中访问中间磁态是具有挑战性的.
研究的目的:
- 为了研究连接物修饰对单核单二烯复合物的磁性特性的影响.
- 探索进入超出典型的性复合体之外的新磁态的可能性.
- 开发新的多态分子开关.
主要方法:
- 新型复合物的合成和表征,其中包括一个修饰的四连接体 (tris(2-pyridylmethyl)amine与一个正方位-anisole部分).
- 可变温度的晶体学,磁性,测热学和光谱学研究.
- 对电子转移和自旋交叉现象的分析.
主要成果:
- 第三个磁性状态,与l.s.一致. CoII (精华素),通过修改连接体来获取.
- 修改后的复合体表现出两步磁切换行为:VT从ls. 科索拉托 (catecholato) 到 l.s. 这是一个很好的选择. CoII (seminquinonato),接下来是从ls的旋转交叉,然后是旋转交叉. 辅助II (seminquinonato) 转换为h.s. 这是一个很好的方法. 子子 (seminquinonato) 是一种子.
- 这代表了在单核单二烯合金复合体中首次观察到两步磁性切换.
结论:
- 连接体设计,特别是结合灵活性或较弱的磁场部分,可以促进进入很少观察到的中间磁状态.
- 观察到的两步磁切换行为突出显示了一条创建先进刺激响应分子开关的新途径.
- 联结体动态性被认为是访问LS的关键因素. CoII状态,这表明了分子开关的新设计标准.
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