捐赠者-接受者的两光子异构性质Stenhouse引证
Francisco A Reza-González1, Emmanuel Villatoro1, Mariana M Reza1
1Instituto de Química, Universidad Nacional Autónoma de México Ciudad de México Mexico jpeon@unam.mx.
Chemical science
|June 2, 2023
概括
捐赠者-接受者斯坦豪斯 adducts (DASAs) 呈现负光色,可以使用两光子吸收来激发. 这使得先进的应用程序,如3D光图和局部药物输送.
科学领域:
- 摄影化学的使用.
- 分子开关 分子开关
- 非线性光学 非线性光学
背景情况:
- 捐赠者-接受者斯坦豪斯 adducts (DASAs) 是光响应分子,以负光色素特征而闻名.
- 现有的应用需要精确的空间控制光反应,通常在可变的深度.
- 非线性光学过程提供了一条实现局部光刺激的途径.
研究的目的:
- 对于增强的两光子吸收特性,研究用扩展的捐赠群体进行捐赠-接受者斯坦豪斯 adducts (DASAs).
- 用 femtosecond激光脉冲来描述这些DASAs的非线性光化学.
- 探索这些分子在先进的光化学应用中的潜力.
主要方法:
- 用扩展的供体群合成DASAs.
- 使用800 nm的女性秒脉冲进行光诱导转换的表征.
- 通过光转换产量测量确定两个光子吸收截面.
- 使用TDDFT和二次响应方法进行理论计算.
主要成果:
- 具有扩展供体的DASA具有显著的两光子吸收特性.
- 在800nm的双光激发会诱导相当于线性吸收的光反应.
- 测量了高达615个GM单位的两光子吸收截面.
- 非线性光化学性质与更高的电子状态和短波长吸收有关.
结论:
- 这项工作报告了DASA中非线性光化学的第一个实例.
- 证明的双光子异体化特性为3D光图案,非线性光刻和局部药物输送打开了道路.
- 这些DASA是目前已知的最非线性活跃的可光切换分子之一.
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