评估基于OPLS的力场,用于研究基于伊米达的二离子液体的特性:用AIMD模拟和实验结果进行比较研究
Zahra Ostadsharif Memar1, Majid Moosavi1
1Department of Chemistry, University of Isfahan, Isfahan 81746-73441, Iran.
The Journal of chemical physics
|December 27, 2023
概括
与其他基于OPLS的力场相比,OPLS-VSIL力场在预测二离子离子液体特性方面显示出最好的一致性. 这项研究评估了结构性,动态性,振动性和体积性质,与初始模拟和实验相比.
科学领域:
- 计算化学的计算化学
- 材料科学 材料科学 材料科学
- 化学物理 化学物理
背景情况:
- 强力场 (FFs) 对离子液体 (ILs) 的分子动力学 (MD) 模拟至关重要.
- 需要精确的FF来预测复杂IL的特性,例如二离子液体 (DIL).
- 现有的基于OPLS的FF需要对其适用于DIL进行评估.
研究的目的:
- 将液体模拟-离子-液体虚拟站点 (OPLS-VSIL) 的优化潜力力力场扩展到基于伊米达的DIL.
- 评估和比较不同基于OPLS的FF (OPLS-2009IL,0.8*OPLS-2009IL,OPLS-VSIL) 对DIL属性的预测能力.
- 评估电荷缩放和部分电荷分布对DIL属性的影响.
主要方法:
- 使用OPLS-2009IL,0.8*OPLS-2009IL和OPLS-VSIL的力场进行了MD模拟,用于[C3(mim) 2][NTF2]2 DIL.
- 进行了初始分子动力学 (AIMD) 模拟以进行比较.
- 分析了结构性 (RDF,结构因子,键网络),动态性 (MSD,范霍夫,离子/子动态),振动性 (IR和功率光谱) 和体积性质.
主要成果:
- 与0.8*OPLS-2009IL相比,OPLS-2009IL和OPLS-VSIL FF在结构性物业方面与AIMD达成了更好的协议.
- OPLS-VSIL和0.8*OPLS-2009IL FFs表现出类似的动态,比OPLS-2009IL更好地与实验结果达成一致.
- 所有FF的振动光谱相似;OPLS-VSIL与实验体积数据略有更好的一致性.
结论:
- 推OPLS-VSIL力场作为评估的基于OPLS的FF中最适合用于模拟[C3(mim) ][NTF2]2 DIL.
- 电荷减少20%会影响动态,但部分电荷分布的影响很小.
- 这项研究验证了OPLS-VSIL用于预测二离子液体的各种特性.
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