2020/11/25 by Atul C. Thakur, Richard C. Remsing
Chemistry · Engineering · Physics and Astronomy · #Chemical physics #Chemistry #Computational chemistry #Dielectric #Dipole #Implicit solvation #Ionic liquid #Materials science #Methane #Microfluidic and Capillary Electrophoresis Applications #Molecular dynamics #Molecule #NMR spectroscopy and applications #Organic chemistry #Partial charge #Physical chemistry #Polarizability #Polarization (electrochemistry) #Quantum, superfluid, helium dynamics #Solvation #Spectroscopy and Quantum Chemical Studies #Water model #cond-mat.stat-mech #physics.chem-ph
paper · pdf · doi:10.1080/00268976.2021.1933228
13 pages, 11 figures
arxiv created 2021/05/08 · openalex publication_date 2021/05/31 · arxiv updated 2021/12/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Liquid hydrocarbons are often modelled with fixed, symmetric, atom-centred charge distributions and Lennard-Jones interaction potentials that reproduce many properties of the bulk liquid. While useful for a wide variety of applications, such models cannot capture dielectric effects important in solvation, self-assembly, and reactivity. The dielectric constants of hydrocarbons, such as methane and ethane, physically arise from electronic polarisation fluctuations induced by the fluctuating liquid environment. In this work, we present non-polarisable, fixed-charge models of methane and ethane that break the charge symmetry of the molecule to create fixed molecular dipoles, the fluctuations of which reproduce the experimental dielectric constant. These models can be considered a mean-field-like approximation that can be used to include dielectric effects in large-scale molecular simulations of polar and charged molecules in liquid methane and ethane. We further demonstrate that solvation of model ionic solutes and a water molecule in these fixed-dipole models improve upon dipole-free models.