Year: 2019
Type: preprint
Abstract: We calculate the effective force between two oppositely charged and similarly charged ions fixed in water as a function of separation distance R. At short separations, R less than 1 nm, the effective force is vastly different from the $1/ε_{s}R^2$ dependence advocated by the screened Coulomb force law (SCFL); $ε_{s}$ being the static dielectric constant of the medium. We also find an interesting asymmetry in the force between +ve and -ve ions. This breakdown of SCFL is shown to be due to the persistent interference between the polarizations created by the two charges, in a manner similar to the vortex-antivortex pair formation in XY model Hamiltonian. The distance dependence of dielectric constants, $ε_{s}$(R) extracted from our simulation exhibit interesting features and can be used in future modelling.
Source: arXiv (Cornell University)
Authors: Banerjee, Puja, Bagchi, Biman
Institution: Indian Institute of Science Bangalore
Language: English
Subfield: Physical and Theoretical Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2910022875