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在阿佐-4-硫尼尔化物中的溶染色体和cis-trans异构体
İsa Sıdır1, Yadigar Gülseven Sıdır2, Halil Berber3
1Department of Physics, Faculty of Sciences and Letters, Bitlis Eren University, 13000, Bitlis, Türkiye. isidir@beu.edu.tr.
概括
在各种溶剂中研究了阿佐-4-硫烯化物 (Azo-SCl) 中的溶染色. 亚-SCl在其两个UV-VIS波段中表现出明显的solvatochromic行为,受溶剂特性的影响,并导致光异构化.
科学领域:
- 摄影化学的使用.
- 物理化学 物理化学
- 频谱学是一种光谱学.
背景情况:
- 阿佐二衍生物以其光色特性和solvatochromism而闻名.
- 了解溶剂对电子转换的影响对于设计功能分子至关重要.
- 阿佐-4-硫烯化物 (Azo-SCl) 是一种在材料科学中具有潜在应用的分子.
研究的目的:
- 在各种溶剂中研究阿佐-4-硫化 (Azo-SCl) 的溶染色.
- 阐明电子转换的性质及其与溶剂性质的相互作用.
- 在紫外线照射下研究Azo-SCl的光异构化行为.
主要方法:
- 紫外线光谱学被用来研究Azo-SCl在一系列溶剂中的电子转换.
- 使用溶解能量模型 (Catalán和Kamlet-Taft) 来分析溶解色变化.
- 量子化学计算,包括时间依赖密度函数理论 (TD-DFT),支持实验数据的解释.
主要成果:
- -SCl表现出两个长波长波段 (321-330nm和435-461nm),对应于π*-π和π*-n过渡.
- 波段I显示了溶解色态的反转 (从负到正),介电常数增加,而波段II始终显示负溶解色态.
- 紫外线照射诱导了快速的trans-cis光异构化,在黑暗中快速的热回归到trans形式.
结论:
- 溶剂的双极性/极化性和键对Azo-SCl.的S2和S1兴奋状态有不同的影响.
- 观察到的solvatochromic行为是由于溶剂在激发状态上的竞争稳定和不稳定作用的结果.
- -SCl经历了高效的光异构化,突出了其作为光响应材料的潜力.
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