Dependence on the thermodynamic state of self-diffusion of pseudo hard-spheres

L. Marchioni; M. A. Di Muro; M. Hoyuelos

doi:10.1103/physreve.107.014134

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arXiv · 2204.12969

Dependence on the thermodynamic state of self-diffusion of pseudo hard-spheres

L. Marchioni·M. A. Di Muro·M. Hoyuelos

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Abstract

Self-diffusion, $D$, in a system of particles that interact with a pseudo hard sphere potential is analyzed. Coupling with a solvent is represented by a Langevin thermostat, characterized by the damping time $t_d$. The hypotheses that $D=D_0 \varphi$ is proposed, where $D_0$ is the small concentration diffusivity and $\varphi$ is a thermodynamic function that represents the effects of interactions as concentration is increased. Molecular dynamics simulations show that different values of the noise intensity modify $D_0$ but do not modify $\varphi$. This result is consistent with the assumption that $\varphi$ is a thermodynamic function, since the thermodynamic state is not modified by the presence of damping and noise.

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BibTeX RIS

L. Marchioni, M. A. Di Muro, M. Hoyuelos. 2022-04-27. Dependence on the thermodynamic state of self-diffusion of pseudo hard-spheres. https://doi.org/10.1103/physreve.107.014134

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