通过替代效应微调多轨道导体的性能
Aaron Mailman1, Joanne W L Wong1, Stephen M Winter1
1Department of Chemistry, University of Waterloo , Waterloo, Ontario N2L 3G1, Canada.
Journal of the American Chemical Society
|January 25, 2017
概括
将一个基组纳入bisdithiazolyl基稳定了LUMO,增强了电荷传输和降低了库伦壁垒. 这导致了Mott绝缘基态,可以调整到压力下的金属行为.
科学领域:
- 材料科学
- 固态化学
- 有机电子
背景情况:
- 氧桥 bisdithiazolyl 基呈现低的 LUMO 水平, 对于固态电荷传输至关重要.
- 通过改变基底联体的电子捐赠或接受特征,可以调节电子性质,包括电荷传输.
研究的目的:
- 调查纳入一个基对 bisdithiazolyl 基的电子结构和电荷传输特性的影响.
- 探索这些激进材料的固态行为和压力依赖导电性.
主要方法:
- 替代 bisdithiazolyl 基的合成和表征
- 用X射线结晶学来确定酸盐的结晶结构.
- 电化学测量 (Ecell) 和磁性敏感性 (χTIP) 研究.
- 高压结晶学和导电性测量
- 密度功能理论 (DFT) 带结构计算.
主要成果:
- 基组的加入显著稳定了LUMO,降低了有效的库伦壁垒 (Ueff) 和电化学电池潜力 (Ecell).
- MeCN溶酸盐形成1D π堆叠阵列,表现出波利磁性和莫特绝缘体的电荷传输特征 (σRT ≈ 0.04 S cm−1,Eact = 0.05 eV).
- 高压导电性测量显示电荷间隙接近6GPa,从Mott绝缘体转向金属状态.
结论:
- 基功能化是一种有效的策略,用于调整双基系统中的电子特性和增强电荷传输.
- 1D π 堆叠结构促进了电荷的传输,作为一个对压力敏感的 Mott 绝缘体.
- 这些发现为设计用于电子应用的有机材料和理解压力诱导的相变提供了洞察力.
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