合成,电子结构,分子包装/形态演变以及纯基/多基基烯的载体流动性
Lei Zhang1, Nicholas S Colella, Feng Liu
1Department of Polymer Science and Engineering, Conte Research Center, University of Massachusetts, Amherst, Massachusetts 01003, USA.
Journal of the American Chemical Society
|December 13, 2012
概括
单分散联的小聚二显示出更好的电荷传输与减少链条长度,由结晶性和晶体的方向驱动,而不仅仅是分子重量. 这有助于我们更好地了解类半导体.
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:
- 单分散联寡二是多分散聚合物的重要模型系统.
- 它们具有独特的光学,光电子和电荷传输特性.
研究的目的:
- 合成和表征多达六个二二甲基四甲基 (DDQT) 单位的单分散的寡甲基.
- 研究它们的电子结构,分子包装,形态和电荷运输.
- 将这些特性与结合长度和分子量相关联.
主要方法:
- 用不同的DDQT重复单元合成寡质.
- 对分子构造和包装进行X射线晶体结构分析.
- 牧场发生率X射线散射用于薄膜形态.
- 收费运输测量 (例如移动性).
主要成果:
- 在有效的结合长度下,电子结构汇聚为聚3,3"-二二四二烯 (PQT-12) .
- 奥利戈提奥芬显示了syn-conformations和曲的基链,以最大限度地减少硬质障碍.
- 形态学从小分子类演变为类似聚合物的包装,接近有效的结合长度.
- 随着链条长度的减少,载荷载体的移动性增加.
结论:
- 载体的移动性主要由结晶性和晶粒误导方向决定,而不仅仅是分子重量.
- 优化结晶性和内平面方向是提高低分子量寡二移动性的关键.
- 建立了对联长度,分子包装和在寡二烯半导体中的电荷传输之间的基本联系.
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