Charge transfer and polarisability in ionic liquids: a case study

Autor: Frederik Philippi, Kateryna Goloviznina, Zheng Gong, Sascha Gehrke, Barbara Kirchner, Agílio A. H. Pádua, Patricia A. Hunt
Přispěvatelé: Laboratoire de Chimie - UMR5182 (LC), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), ANR-16-IDEX-0005,IDEXLYON,IDEXLYON(2016)
Jazyk: angličtina
Rok vydání: 2022
Předmět:
Zdroj: Physical Chemistry Chemical Physics
Physical Chemistry Chemical Physics, 2022, 24 (5), pp.3144-3162. ⟨10.1039/d1cp04592j⟩
ISSN: 1463-9076
1463-9084
DOI: 10.1039/d1cp04592j⟩
Popis: The practical use of ionic liquids (ILs) is benefiting from a growing understanding of the underpinning structural and dynamic properties, facilitated through classical molecular dynamics (MD) simulations. The predictive and explanatory power of a classical MD simulation is inextricably linked to the underlying force field. A key aspect of the forcefield for ILs is the ability to recover charge based interactions. Our focus in this paper is on the description and recovery of charge transfer and polarisability effects, demonstrated through MD simulations of the widely used 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide [C4C1im][NTf2] IL. We study the charge distributions generated by a range of ab initio methods, and present an interpolation method for determining atom-wise scaled partial charges. Two novel methods for determining the mean field (total) charge transfer from anion to cation are presented. The impact of using different charge models and different partial charge scaling (unscaled, uniformly scaled, atom-wise scaled) are compared to fully polarisable simulations. We study a range of Drude particle explicitly polarisable potentials and shed light on the performance of current approaches to counter known problems. It is demonstrated that small changes in the charge description and MD methodology can have a significant impact; biasing some properties, while leaving others unaffected within the structural and dynamic domains.
Databáze: OpenAIRE