在MOF中的吸附预测上量化力场选择的不确定性
Connaire McCready1, Kristina Sladekova1, Stuart Conroy1
1Department of Chemical and Process Engineering, University of Strathclyde, 75 Montrose Street, Glasgow G1 1XJ, United Kingdom.
Journal of chemical theory and computation
|May 31, 2024
概括
在金属有机框架 (MOF) 中模拟吸附是具有挑战性的,因为实验的可变性和未经验证的力场. 这项研究量化了模拟不确定性,揭示了标准模型对于某些MOF系统可能会严重失败.
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
- 化学工程是化学工程的重要组成部分.
背景情况:
- 在金属有机框架 (MOF) 中比较模拟和实验性吸附异热体面临着重大挑战.
- 实验数据显示出相当大的差异,异常值占公布结果的20%左右.
- 模拟力场经常在没有验证的情况下使用,它们对吸附预测可靠性的影响还没有得到很好的量化.
研究的目的:
- 系统量化吸附等温预测中的不确定性,这些不确定性来自MOF中的力场选择.
- 独立研究框架莱纳德-斯参数对甲吸附的影响,最大限度地减少静电相互作用.
- 通过解决数据变化和异常值,提供模拟和实验吸附数据之间的严格比较.
主要方法:
- 开发了一种方法来量化模拟吸附异热体中因力场选择而产生的不确定性.
- 专注于原型MOF中的甲吸附,以隔离莱纳德-斯参数的影响.
- 从模拟中计算出一个共识等热量,用不确定性量化.
- 从文献中手动策划和统计分析实验吸附数据,删除异常值.
主要成果:
- 在模拟的吸附异热体中,不确定性可达15%.
- 标准力场为一些MOF系统提供可靠的预测.
- 标准力场存在显著的系统性缺陷,导致其他MOF系统的预测失败.
结论:
- 强场选择在模拟的吸附异热体中引入了相当大的不确定性.
- 目前的标准力场对于MOF吸附预测并不普遍可靠.
- 为未来的模拟提供了建议,包括对MOF的高通量计算选.
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