极子,双极子,并排极子在减少的化物
Lori Zaikowski1, Parmeet Kaur, Claudia Gelfond
1Chemistry and Physics Department, Dowling College, Oakdale, NY, USA.
Journal of the American Chemical Society
|June 7, 2012
概括
研究合聚合物揭示了电荷载体形成极子. 较长的聚合物链表现出两个相邻的极子,不同于较短的链.
科学领域:
- 有机化学 有机化学
- 材料科学 材料科学 材料科学
- 频谱学是一种光谱学.
背景情况:
- 结合聚合物在有机电子学中至关重要.
- 了解电荷载体的行为 (极子,双极子) 是它们功能的关键.
- 奥利戈化物 (F(n)) 作为研究这些现象的模型系统.
研究的目的:
- 为了阐明烯寡合体中电荷载体的性质.
- 为了研究在减少时从极子转变为双极子的过渡.
- 将实验结果与理论计算进行比较.
主要方法:
- 光学光谱学 (UV-Vis-NIR) 用于分析单电子和多电子的减少烯寡合物 (F(n),n=1-10).
- 使用了化学还原和脉冲放射溶解技术.
- 进行了密度函数理论 (DFT) 计算,使用长距离校正函数进行了计算.
主要成果:
- 单次还原产生了极子的典型光谱.
- 短小聚合物在双重减少后显示出极子双极子过渡.
- 较长的寡合体表现出两个相邻的极子,占据~4个重复单元,吸收带扩大.
- DFT计算准确地预测了极子,双极子和并排的极子结构,与标准函数不同.
- 在较长的寡合体离子中观察到遗留中性 (VN) 吸收带.
结论:
- 烯寡合体中的电荷载体存在于极子中,较长的链条容纳两个空间分离的极子.
- 电荷载体的行为在很大程度上取决于寡合体的长度.
- 长距离纠正的DFT函数对于准确建模这些系统至关重要.
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