在分子描述的光下,沸点,临界温度和结温度:相关性和因果关系
Ossama Abdeen1, Mohamed Ismael1, Aly Abdou1
1Chemistry Department, Faculty of Science, Sohag University, Sohag, 82524, Egypt. m_ismael@science.sohag.edu.eg.
Physical chemistry chemical physics : PCCP
|January 3, 2024
概括
流体的物理化学性质受到分子相互作用的影响. 平均局部电离能 (ALIE) 和电子定位函数 (ELF) 是沸点和点的关键预测指标,为分子层面提供了新的见解.
科学领域:
- 计算化学的计算化学
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
背景情况:
- 在分子水平上了解液体的物理化学性质对于各种科学和工程应用至关重要.
- 传统的方法往往侧重于静电电位 (EP),但其他分子描述器可能会提供更深入的见解.
- 准确预测诸如沸点和点之类的属性,需要对分子间力量有全面的了解.
研究的目的:
- 研究分子表面特性,特别是平均局部电离能 (ALIE) 和电子定位函数 (ELF) 在确定流体物理化学性能的作用.
- 建立新的基于分子的推理,用于预测正常的沸点和点以及临界温度.
- 为了更深入地了解两极化和保利排斥对分子间相互作用的贡献.
主要方法:
- 在169个分子上进行了*ab initio*分子表面分析,将静电电位 (EP),ALIE和ELF映射到电子密度等平面上.
- 使用渐进线性回归 (SLR) 分析来将分子描述符与物理化学性质相关联.
- 在各种分子复合体上进行了局部化分子轨道能量分解分析 (LMO-EDA),以验证对极化和保利相互作用的发现.
主要成果:
- 逐步线性回归显示,ALIE和ELF是正常沸点和结点以及临界温度的重要预测指标,与EP.
- ALIE与分子之间的有吸引力的极化力相关;较低的ALIE值表明较强的极化相互作用.
- ELF与反射保利力相关;更高的ELF值表明更强的保利力.
结论:
- ALIE和ELF是理解和预测流体物理化学性质的关键分子描述器.
- 这项研究提供了分子层面的解释,解释了两极化和保利力在确定大量流体性质方面的相互作用.
- 这些发现为物理化学家,化学工程师和试图设计和操纵流体的材料科学家提供了宝贵的见解.
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