阿尔干乙醇的TAMie力场:处理稀缺实验数据的多忠度高斯过程
Maximilian Fleck1, Samir Darouich1, Niels Hansen1
1Institute of Thermodynamics and Thermal Process Engineering, University of Stuttgart, Pfaffenwaldring 9, Stuttgart 70569, Germany.
The journal of physical chemistry. B
|September 18, 2024
概括
这项研究增强了乙醇可转移的异构性Mie潜力 (TAMie). 新模型准确地预测了乙醇及其混合物的液体密度,蒸汽压力和相位行为.
科学领域:
- 化学物理 化学物理
- 材料科学 材料科学 材料科学
- 计算化学计算化学
背景情况:
- 精确的分子建模乙醇对于理解它们的物理性质至关重要.
- 现有的模型往往缺乏跨不同乙醇和条件的可转移性和准确性.
- 可转移的异构米电位 (TAMie) 为分子模拟提供了一个有前途的框架.
研究的目的:
- 为了扩展可转移的异构性Mie潜力 (TAMie),以准确地建模乙醇.
- 使用状态和高斯过程方法的分析方程来优化TAMie力场参数.
- 为了验证模型对纯乙醇及其与基的二元混合物的预测.
主要方法:
- 使用状态的分析方程作为替代模型优化TAMie力场参数.
- 用线性多忠实度高斯过程方法补充实验数据中的温度差距.
- 尽量减少C1-C5硫醇计算和实验蒸汽压力和液体密度之间的偏差.
- 对更高的乙醇 (C6,C8) 的可转移性验证和剪切粘度的预测.
- 研究乙醇与基二元混合物的相位行为.
主要成果:
- 对于1-propanethiol,1-butanethiol和1-pentanethiol,在液体密度和蒸汽压力中实现了小的平均绝对相对偏差.
- 证明了力场对更高的乙醇 (1-hexanethiol,1-octanethiol) 的可转移性.
- 为甲乙醇和乙乙醇提供了特定的参数集.
- 预测的剪切粘度与实验数据相符,尽管它不是参数化的一部分.
- 在TAMie模型预测和实验数据之间观察到极好的一致性,用于二元乙醇-混合物的相位行为.
结论:
- 扩展的TAMie模型为alkanethiols提供了准确和可转移的力场参数.
- 该模型成功地预测了纯乙醇及其混合物的热物理性质和相位行为.
- 这项工作为设计和模拟涉及乙醇的系统提供了有价值的计算工具.
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