通过线性反应方法的兴奋子吸收光谱:应用于合聚合物
Martín A Mosquera1, Nicholas E Jackson1,2, Thomas J Fauvell1
1Department of Chemistry and the Materials Research Center, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208, United States.
Journal of the American Chemical Society
|February 23, 2017
概括
这项研究提出了一种有效的两步方法来计算合聚合物的激子光谱. 这种新方法准确地预测近红外吸收,有助于了解材料特性,并指导未来的光谱发展.
科学领域:
- 计算化学
- 光谱学
- 材料科学
背景情况:
- 计算激子光谱对于理解材料中的激态动态至关重要.
- 传统的方法面临着使用常见密度函数的计算成本和准确性的挑战.
- 之前的工作引入了两步计算来解决这些限制.
研究的目的:
- 应用一种新的两步理论方法来计算激子的近红外吸收光谱.
- 研究聚3-基烯 (P3HT),聚2-甲-5-基烯 (MEH-PPV) 和聚-基烯-基烯 (PTB7) 的寡合体中的激素行为.
- 确定主导轨道激发,并建立预测最长波长吸收峰值的规则.
主要方法:
- 一个两步计算,涉及两个线性响应时间依赖密度函数理论 (TDDFT) 步骤.
- 第一个TDDFT步骤产生被激发状态扰乱的轨道.
- 第二个TDDFT步骤计算了相对于激发状态的激发光谱.
主要成果:
- 对P3HT和MEH-PPV寡合物的计算光谱显示了10个单体单位的趋同,与实验数据保持一致.
- 在MEH-PPV中发现刺激的光谱特征与双色球形成重叠.
- 在短暂的吸收光谱中确定了PTB7寡合体中的兴奋剂吸收波段.
- 在所有研究的聚合物中报告了对光学活跃转换有助于形成的主导轨道刺激.
结论:
- 开发的方法准确地预测合聚合物中激子的近红外吸收光谱.
- 这些发现为激素-双极相互作用提供了洞察力,并验证了实验中的短暂吸收光谱.
- 该方法为先进的理论短暂光谱学提供了基础,包括非相应效应和电荷转移状态.
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