Single-chain simulation of Ising density functional theory for weak polyelectrolytes

Alejandro Gallegos; Marcus Müller; Jianzhong Wu

doi:10.1063/5.0175561

Single-chain simulation of Ising density functional theory for weak polyelectrolytes

J Chem Phys. 2023 Dec 7;159(21):214902. doi: 10.1063/5.0175561.

Authors

Alejandro Gallegos¹, Marcus Müller², Jianzhong Wu¹

Affiliations

¹ Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, USA.
² Institut für Theoretische Physik, Georg-August-Universität, 37077 Göttingen, Germany.

PMID: 38047517
DOI: 10.1063/5.0175561

Abstract

Conventional theories of weak polyelectrolytes are either computationally prohibitive to account for the multidimensional inhomogeneity of polymer ionization in a liquid environment or oversimplistic in describing the coupling effects of ion-explicit electrostatic interactions and long-range intrachain correlations. To bridge this gap, we implement the Ising density functional theory (iDFT) for ionizable polymer systems using the single-chain-in-mean-field algorithm. The single-chain-in-iDFT (sc-iDFT) shows significant improvements over conventional mean-field methods in describing segment-level dissociation equilibrium, specific ion effects, and long-range intrachain correlations. With an explicit consideration of the fluctuations of polymer configurations and the position-dependent ionization of individual polymer segments, sc-iDFT provides a faithful description of the structure and thermodynamic properties of inhomogeneous weak polyelectrolyte systems across multiple length scales.