在高度定义的二胺四倍 π 堆中,超快速激素移位,局部化和排泄物形成的动态
Christina Kaufmann1, Woojae Kim2, Agnieszka Nowak-Król1
1Universität Würzburg , Institut für Organische Chemie & Center for Nanosystems Chemistry , Am Hubland , 97074 Würzburg , Germany.
Journal of the American Chemical Society
|March 6, 2018
概括
一种新型的烯二氧化物 (PBI) 二聚体, Bis-PBI,自组合成四个染色体堆. 超快速动态显示激素连贯性和放松的快速丧失,使其处于激酶体状态.
科学领域:
- 超分子化学
- 光物理学
- 有机材料
背景情况:
- 二氧化物 (PBIs) 是具有可调节光物理性能的多功能色素.
- 为了开发先进的有机材料,PBI衍生品的自组装至关重要.
- 了解PBI聚合物的激发动态是控制能量转移和光采集过程的关键.
研究的目的:
- 合成和表征一个海湾绑定烯二氧化物 (PBI) 模体, Bis-PBI.
- 研究Bis-PBI的自我组装行为和聚合结构.
- 阐明自组装 Bis-PBI 四重堆中的超快激子动态和放松路径.
主要方法:
- 对于Bis-PBI合成的Pd/Cu催化格拉泽型氧化同.
- 稳定状态吸收和发射光谱以描述光学特性.
- 宽带光向上转换光谱 (FLUPS) 和短暂吸收光谱来研究激发状态的动态.
主要成果:
- 双-PBI二聚体合成并自组合成具有高结合常数 (高达10^6 M^-1) 的四种染色体的离散π.
- 在四重堆中显示H型激发性合.
- FLUPS揭示了超快的连贯性损失 (τ ≈ 200 fs) 从非局部化的弗伦克尔激发状态到激发状态.
- 在短四倍堆中观察到没有连贯的激素传播和多激素生成.
结论:
- 合成的Bis-PBI二聚体形成了明确的H-聚合物.
- 由于总体长度较短,激发动态主要由快速的连贯性丧失和放松到激发体状态主导.
- 四重堆结构限制了连贯的激素传播,并阻止了多重激素的产生.
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