两个状态的"开启-关闭"NLO切换Rh (III) - 二复合物的理论视角,具有相当大的第一个超极化性
Huiying Wang1,2, Feiwu Chen1,2
1Department of Chemistry and Chemical Engineering, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing 100083, China.
The journal of physical chemistry. A
|June 5, 2023
概括
这项研究分析了Rh(III) - 二复合体,发现变形体表现出增强的电荷分离和π-结合. 这些复合体表现出显著的非线性光学 (NLO) 特性,表明潜在的光电子应用.
科学领域:
- 计算化学计算化学
- 材料科学 材料科学 材料科学
- 光电学是指光电子产品.
背景情况:
- 亚烯复合物以其光异构化能力而闻名.
- Rh (III) 复合体具有独特的电子和几何性质.
- 了解结构属性关系对于设计先进材料至关重要.
研究的目的:
- 为了研究光诱导的Rh(III) -阿佐烯复合体在cis-和trans-conformations中的几何和电子结构.
- 分析线性和二次非线性光学 (NLO) 属性.
- 探索它们的紫外线吸收光谱,以寻找潜在的光电子应用.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 对几何和电子结构的分析.
- 计算NLO特性 (第一个超极化,βtot) 和紫外线对紫外线的吸收光谱.
主要成果:
- 与cis-Rh相比,Trans-Rh形态表现出优越的电荷分离和π-结合.
- 两种 cis-和 trans-Rh 构造都显示出异常小的能量间隙 (0.28-0.36 eV),促进电子过渡.
- 观察到相当大的二级NLO反应,βtot值高达8.5 × 104 a.u. 对于跨-Rh (ON状态).
- 一个可切换比为1.2的βtot表示明确的切换特征.
- 紫外线光谱在紫外线 (cis-Rh,301 nm) 和可见光 (trans-Rh,446 nm) 区域显示出明显的吸收峰值,允许调节的吸收.
结论:
- 研究的Rh(III) - 二复合物由于其电子结构和小的能量差距,具有显著的NLO特性.
- cis-和trans-forms的独特吸收概况使可调节的光学响应成为可能.
- 这些发现突显了Rh(III) -azo复合体在光电子设备中的潜力.
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