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在单分子结合处的悬浮跨协调的导电和热电行为 (II) 复合体
Pablo Bastante1, Ross J Davidson2, Wafa Al Malki3
1Departamento de Física de la Materia Condensada C-III, and Instituto Universitario de Ciencia de Materiales "Nicolás Cabrera", Universidad Autónoma de Madrid, E-28049 Madrid, Spain.
ACS omega
|September 16, 2024
概括
带有异构体连接体的合体复合体在分子连接处表现出改变的电子运输. 金属协调通过缩小能量差距来提高导电性和西贝克系数.
科学领域:
- 协调化学 协调化学
- 分子电子学分子电子学
- 表面科学是一门学科.
背景情况:
- 研究分子结构对电子传输特性的影响对于推进分子电子学至关重要.
- 金属复合体中的连接体的连接性可以显著影响它们在单分子结处的电子行为.
研究的目的:
- 探索同位素1,2-bis(2-pyridylethynyl) (bpb) 复合物的连接性如何影响电子传输.
- 了解金属协调在调节这些分子系统的导电和热电特性中的作用.
主要方法:
- 合成两个同位素配体: 2,2'-((4,5-bis(hexyloxy) -1,2-烯) -2,2-乙烯-2,1-二烯)) -4-甲基) -4-甲基) 和 6,6'-((4,5-bis(hexyloxy) -1,2-) -2-乙烯-2,1-二烯)) -3-甲基) -3-甲基).
- 与PdCl2的协调形成跨-Pd(L) Cl2复合体.
- 使用X射线光电子谱学 (XPS) 进行接触模式的表征.
- 使用扫描道显微镜断路结 (STM-BJ) 和密度函数理论 (DFT) 计算的测量.
主要成果:
- 与甲联同体相比,与甲联同体相比,甲联同体的典型较低导电性在金属协调后被抑制.
- 观察到电导率和Seebeck系数的适度增加.
- 这种增强归因于最高占有分子轨道-最低未占有分子轨道 (HOMO-LUMO) 间隙的收缩.
结论:
- 在异构型bpb合金复合体中的金属协调可以克服meta和para异构体之间的固有导电率差异.
- 观察到的电导率和Seebeck系数的增加与减少的HOMO-LUMO差距有关.
- 与分子共振相对的费米能量是影响西贝克系数的关键因素.
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