在概念密度函数理论中的温度和外部场
Marco Franco-Pérez1, Farnaz Heidar-Zadeh2, Paul W Ayers3
1Departamento de Física y Química Teórica, Facultad de Química, Universidad Nacional Autónoma, de México, Cd Universitaria Ciudad de México Mexico.
Chemical science
|November 21, 2024
概括
概念 DFT (CDFT) 现在包含温度和外部场,增强化学反应性描述器. 这个扩展解决了N-区分性问题,并引入了新的热力学反应性概念,用于更好的分子合成和分析.
科学领域:
- 理论化学 理论化学
- 计算化学计算化学
- 量子化学 是一个量子化学.
背景情况:
- 概念密度函数理论 (CDFT) 传统上依赖于依赖电子数 (N) 和外部电位 (v) 的能量函数.
- CDFT的优势在于它能够适应并纳入额外的状态变量.
- 最近的进展需要扩展CDFT以解决复杂的化学系统和反应.
研究的目的:
- 将温度和外部场 (电,磁,机械,压力) 纳入CDFT中的基本变量.
- 开发新的,良好的化学反应性描述器,包括热力学概念和全球描述器的本地类型.
- 探索这些新变量对化学选择性和特性的影响.
主要方法:
- 利用大法典乐团引入有限温度,减轻了N-区别性问题.
- 将能量函数扩展到包括外部场 (X),定义类似于经典热力学的响应函数.
- 在各种外部场和机械力下分析了电负性和硬度的行为.
主要成果:
- 有限温度引入了新的热力学反应性描述器,如热容量,并有助于定义局部硬度.
- 外界场,像电场一样,诱导反应通道的选择性 (例如,福井函数).
- 原子的电子阴性和硬度在磁场中表现出零碎的行为,并在机械力和压力下发生变化,与结构和体积演变相关联.
结论:
- 将CDFT扩展到温度和外部场提供了一个更全面的框架来理解化学反应.
- 开发的描述符为在各种实验条件下分子行为提供了新的见解.
- 这些进展对于设计和合成具有定制性质的新型分子至关重要.
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