在单核铁 (II) 复合体中,跨配置的干增强旋转交叉到室温
Guang-Wen Fu1, Yan Kong1, Xin Chen1
1Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials, School of Chemistry and Material Science, Jiangsu Normal University, Xuzhou, 221116, China.
Chemistry, an Asian journal
|July 21, 2025
概括
合成了七种新的铁复合物,并研究了旋转交叉 (SCO) 特性. 综合体3具有转换配置,显示了增强的SCO特征,突出显示了连接体对旋转转换的影响.
科学领域:
- 协调化学 协调化学
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
背景情况:
- 旋转交叉 (SCO) 复合体是可以在低旋转和高旋转状态之间切换的材料,为先进的电子设备提供了潜力.
- 连接体环境显著影响铁 (II) 复合物的SCO特性,包括过渡温度和合作性.
- 了解分子结构和SCO行为之间的关系对于设计新型功能材料至关重要.
研究的目的:
- 合成和表征七种新的单核铁 (II) 复合物,具有不同的配体:8-氨基诺林 (aqin),2-皮科利胺 (2-pic) 和tris2-pyridylmethyl) 胺 (tpa).
- 研究这些复合物的结构和磁性特性,特别是自旋交叉 (SCO) 行为.
- 阐明连接体场强度和分子配置 (cis 与 trans) 对 SCO 过渡温度 (T1/2) 的影响.
主要方法:
- 合成和单晶X射线衍射以确定铁 (II) 复合物的精确分子结构.
- 测量磁感应度以确定SCO行为并确定过渡温度 (T1/2).
- 理论计算,包括高斯和DFT+U+D3方法,以建模电子结构并合理化观察到的SCO现象.
主要成果:
- 成功合成了七个新的单核铁 (II) 复合物: [Fe ((aqin) 2 ((NCS) 2) ] (1), [Fe ((aqin) 2 ((NCSe) 2)) (2), [Fe ((aqin) 2 ((NCBH3) 2)) (3), [Fe ((2-pic) 2 ((NCS) 2)) (4), [Fe ((2-pic) 2 ((NCSe) 2)) (5), [Fe (((2-pic) 3)) (6),和 [Fe ((tpa) 2)) (7).
- 综合体1,2和4仍然处于高旋转状态,而综合体3,5,6和7呈现SCO,其T1/2值分别为310K,162K,262K和400K.
- 复合体3具有转变配置,与相关的cis配置复合体相比,显示出异常高的T1/2 (310K),这归因于结构扭曲减少和LS稳定.
结论:
- 晶体结构 (cis vs. trans) 显著影响铁复合体的自旋交叉特性.
- 复合体3的转换配置导致SCO行为增强,过渡温度接近室温.
- 理论建模支持实验结果,表明跨复合体中减少的扭曲会稳定低旋转状态,增加T1/2.2.
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