Exploring the structural feature of water, alcohols, and their binary mixtures with concrete atomic charge assignments in Dreiding forcefield

• Published in: Journal of molecular graphics & modelling Vol. 133; p. 108863
• Main Authors: Zhuang, Chen, Ji, Haoli, Xu, Antian, Chai, Muyuan
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-12-2024
• Subjects: Alcohols - chemistry; Atomic charge; Density and structure; Dreiding forcefield; Hydrogen Bonding; Molecular Dynamics Simulation; Solvents - chemistry; Water - chemistry; Water and alcohols; Density and structure; Molecular dynamics simulation; Water and alcohols; Dreiding forcefield; Atomic charge
• ISSN: 1093-3263; 1873-4243; 1873-4243
• DOI: 10.1016/j.jmgm.2024.108863

The water, alcohols, and their binary mixtures are widely used in molecular simulations. However, the Dreiding force field lacks a generally accepted method for assigning atomic charges to these solvents during simulations. In this study, we propose a universal charge assignment for water and eight water-miscible alcohols in Dreiding. Through extensive molecular simulations, we demonstrate the good accuracy of our charge assignments in displaying characteristic of these solvents and their mixtures, including liquid density and structure. Moreover, we investigate equilibrium snapshot, radial distribution function, coordination number and hydrogen bonding, all of which confirm the miscibility of alcohols with water or ethanol. Notably, we reveal that the structure diversity among different mixtures can be attributed to distinctive characteristic of alcohols, including molecular volume, as well as the number and position of hydroxyls.
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•A general rule of atomic charge assignment for water and alcohols in Dreiding forcefield were proposed and validated.•Density and structure of water/alcohol solvents and their binary mixtures were confirmed appropriate.•Molecular volume and number and position of hydroxyls were revealed of great influence on the structural features.