Is the Local Ion Density Sufficient to Drive NaCl Nucleation from the Melt and Aqueous Solution?

• DOI: 10.1021/acs.jpcb.3c06735
• Publication Date: 2024-01-23T23:43:41Z
• Authors: Ruiyu Wang; Shams Mehdi; Ziyue Zou; Pratyush Tiwary
• Keywords: Reaction coordinate; Umbrella sampling

Even though nucleation is ubiquitous in different science and engineering problems, investigating extremely difficult due to the complicated ranges of time length scales involved. In this work, we simulate NaCl both molten aqueous environments using enhanced sampling all-atom molecular dynamics with deep-learning-based estimation reaction coordinates. By incorporating various structural order parameters learning coordinate as a function thereof, achieve significantly improved relative traditional ad hoc descriptions what drives nucleation, particularly an medium. Our results reveal one-step mechanism environments, analysis highlighting importance local ion density distinguishing solid liquid states. However, although fluctuations are necessary drive they not sufficient. shows that near transition states, descriptors such enthalpy structure become crucial. protocol proposed here enables robust phase could offer insights into mechanisms for generic small molecules environments.