准备和表征pi堆叠的二甲寡甲. 从晶体结构和分子轨道计算中预测半导体行为和带宽
Daron E Janzen1, Michael W Burand, Paul C Ewbank
1Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA.
Journal of the American Chemical Society
|November 19, 2004
概括
新的奇诺类寡基对有机电子产品显示出前景. 它们的平面结构和pi堆叠使单维电子带结构成为可能,这表明薄膜晶体管中具有高电荷载体移动性的潜力.
科学领域:
- 有机电子学有机电子学
- 材料科学是一种材料科学.
- 固态物理 固态物理
背景情况:
- 昆类寡二被研究其在有机电子设备中的潜力.
- 之前的研究表明,相关化合物的高流动性和双极运输.
- 了解结构属性关系对于设计先进的有机半导体至关重要.
研究的目的:
- 合成和表征新的二甲替代的三二烯和四二烯寡合物.
- 为了比较它们的电子和结构性质与以前研究过的类寡甲.
- 为了阐明分子结构对电荷传输行为的影响.
主要方法:
- 新型化硫衍生物的合成.
- 电化学分析 (氧化和还原潜力).
- 紫外-对-红外光谱法用于确定光学特性.
- 用X射线结晶学进行结构确定.
- 用于电子带结构分析的分子轨道计算.
主要成果:
- 合成的寡合物在特定的潜在范围内表现出可逆的氧化还原行为.
- 在UV-Vis-NIR光谱中观察到的强烈的低能量pi-pi转换 (lambda (max) 648-790 nm).
- X射线结构显示平面脊柱和短的分子间pi堆叠距离 (3.335-3.492 A).
- 分析表明由于pi堆叠而导致的一维电子带结构.
- 计算的带宽表明了显著的孔和电子流动性.
结论:
- 新的状寡基具有有利于有机电子的电子和结构性质.
- 分子间的pi堆叠是实现一维电子带结构的关键因素.
- 这些化合物代表了高性能薄膜晶体管应用的有希望的候选者.
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