Work

Density Functional Theory of Ionic Screening: When Do Like Charges Attract?

Year: 1990

Type: article

Abstract: We describe a simple local density functional theory for screened interactions between macroions and apply it to electric double layers. The approach incorporates the strong correlations between screening ions at high densities, and reduces to the Poisson-Boltzmann equations at low densities. Results for monovalent ions are in excellent agreement with Monte Carlo (MC) and inhomogeneous hypernetted chain (IHNC) calculations. Nonlocal effects are important for divalent ions at small macroion separations and high surface charge densities. A simple weighted density approximation qualitatively reproduces MC and IHNC results in this regime, and provides a simple explanation for the onset of attractive interactions between like-charged plates.

Source: Europhysics Letters (EPL)

DOI: 10.1209/0295-5075/12/1/015

Authors: M. J Stevens, M. O Robbins

Institutions: Johns Hopkins University, University of California, Santa Barbara, Kavli Institute for Theoretical Physics

Language: English

Topic: Electrostatics and Colloid Interactions

Subfield: Physical and Theoretical Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: bronze

Funders: National Science Foundation, Alfred P. Sloan Foundation

Awards: Presidential Young Investigator Award, Institute for Theoretical Physics