结合色素子阵列具有异常大的孔极子移位长度
Kimihiro Susumu1, Paul R Frail, Paul J Angiolillo
1Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104-6323, USA.
Journal of the American Chemical Society
|June 29, 2006
概括
我们使用EPR光谱学研究了(II) 氨酸寡合体 (PZnn) 中的离子基态. 这些材料表现出前所未有的长度和温度不变的孔极子移位,验证了长距离的电荷跳跃模型.
科学领域:
- 材料科学 材料科学 材料科学
- 频谱学是一种光谱学.
- 有机电子 有机电子
背景情况:
- (II) 氨酸 (PZnn) 寡合体的meso-to-meso乙烯桥梁研究了它们的电子性质.
- 了解这些扩展联系统中的电荷移位对于开发新的电子材料至关重要.
研究的目的:
- 通过使用可变温度X波段电子偏磁共振 (EPR) 光谱,研究PZnn寡合体在离子基态中的电荷载体移位.
- 为了确定孔极点移位的长度尺度和温度依赖性.
主要方法:
- 可变温度 (4298 K) X带EPR光谱对PZnn寡合体 ([PZn2-PZn7]+) 进行.
- 使用EPR线宽的分析 (DeltaBp-p) 来量化孔极点移位.
- 数据是使用一个随机的,一维的电荷跳跃模型建模的.
主要成果:
- PZnn+寡合物表现出迄今为止测量到的最大孔极子移位长度,延伸到大约75 Å.
- 发现,在研究范围内的电荷移位长度与温度不变.
- 实验EPR数据强烈支持诺里斯型洞移位机制.
结论:
- 在显著的长度尺度上,PZnn寡合体表现出强大的孔移位机制,挑战了传统的电荷定位理论.
- 这些发现表明,聚合物构件中较低的内部球体重组能量是实现先进电子材料中长极子移位的关键.
- 这些寡合体中的极子跳跃率异常高,即使在低温下也超过10^7 s^-1.
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