Atypical violation of the Stokes–Einstein relation in a dense binary Lennard–Jones mixture
- Authors: Das S.1, Priya M.1
-
Affiliations:
- Birla Institute of Technology
- Issue: Vol 121, No 3-4 (2025)
- Pages: 226-227
- Section: Articles
- URL: https://journal-vniispk.ru/0370-274X/article/view/286088
- DOI: https://doi.org/10.31857/S0370274X25020092
- EDN: https://elibrary.ru/AWVIQD
- ID: 286088
Cite item
Abstract
We study the dynamics of particles in binary mixtures near the freezing transition using molecular dynamics simulations. The particles are considered to interact via a Lennard-Jones potential, and the impact of varying their size-ratio on their dynamics is examined. By calculating the mean-squared displacements and the self-intermediate scattering function of the particles, we find that introducing size disparity in an equimolar mixture at a constant packing fraction hinders particle movement, leading to a decrease in the self-diffusion coefficient. Additionally, as the size disparity increases, the local cage relaxation time becomes longer. Interestingly, the increase in the system’s viscosity does not correspond to an expected decrease in self-diffusion, resulting in an unusual violation of the Stokes-Einstein relation. Unlike typical glass-forming mixtures, where this violation parameter increases as temperature decreases, we observe the opposite behaviour.
About the authors
Sh. Das
Birla Institute of Technology
Author for correspondence.
Email: madhupriya@bitmesra.ac.in
Department of Physics
Mesra, IndiaM. Priya
Birla Institute of Technology
Email: madhupriya@bitmesra.ac.in
Department of Physics Mesra, India
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