第二代材料的计算设计中的共价有机框架:四原子的作用及其相互作用
Irina D Yushina1, Artëm E Masunov2,3, Ekaterina V Bartashevich1
1South Ural State University, Lenin pr. 76, Chelyabinsk 454080, Russia.
The journal of physical chemistry. A
|September 12, 2024
概括
计算研究揭示了共价有机框架 (COF) 中不同中心四原子 (碳,,) 和替代物如何影响非线性光学特性. 电子密度的变化影响着四结合和光学响应.
科学领域:
- 材料科学 材料科学 材料科学
- 计算化学的计算化学
- 固态物理 固态物理
背景情况:
- 设计先进的非线性光学 (NLO) 材料通常需要计算建模.
- 共价有机框架 (COF) 是NLO应用的有希望的材料.
- 了解结构-属性关系对于定制COF性能至关重要.
研究的目的:
- 研究COF-102家族材料中中央四原子 (C,Si,Ge) 的影响.
- 检查素替代 (Cl,Br,I) 对分子内四结合的作用.
- 为了将电子结构的变化与非线性光学特性相关联,特别是二次电感受性 (χ(2)).
主要方法:
- 密度函数理论 (DFT) 的计算.
- 在中心四原子周围电子密度分布的分析.
- 定期电偶扰动的Kohn-Sham (CPKS) 方法用于计算 χ(2).
主要成果:
- 中心的四原子显著改变了Tt-Car键中的电子移位.
- 在正体位置的素替代会诱导四键和其他非对应相互作用.
- 随着素大小 (H > Cl > Br > I) 的增加,观察到与Tt-Car键延长相关的反直觉降低.
结论:
- 烯原子选择和正极素替代是调整COFs的NLO特性的关键因素.
- 观察到的素大小和NLO反应之间的反向关系突出了复杂的电子效应.
- 这项研究为基于COFs的新型NLO材料的合理设计提供了见解.
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