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arXiv · 0712.2071

First-principles Predictor of the Location of Ergodic-Non-ergodic Transitions

Pedro Esequiel Ramírez-González·Rigoberto Juárez-Maldonado·Laura Yeomans-Reyna·Marco Antonio Chávez-Rojo·Martin Chávez-Páez·Alejandro Vizcarra-Rendón·Magdaleno Medina-Noyola
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Abstract

This letter presents a remarkably simple approach to the first-principles determination of the ergodic-non-ergodic transition in monodisperse colloidal suspensions. It consists of an equation for the long-time asymptotic value $γ$ of the mean squared displacement of the colloidal particles, whose finite real solutions signal the non-ergodic state, and determines the non-ergodic parameter $f(k)$. We illustrate its concrete application to three simple model colloidal systems, namely, hard-spheres, hard-spheres plus repulsive (screened Coulomb) Yukawa interaction, and hard-sphere plus attractive Yukawa tail. The results indicate that this is quite a competitive theory, similar in spirit to, but conceptually independent from, the well-known mode coupling theory.

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Pedro Esequiel Ramírez-González, Rigoberto Juárez-Maldonado, Laura Yeomans-Reyna, Marco Antonio Chávez-Rojo, Martin Chávez-Páez, Alejandro Vizcarra-Rendón, Magdaleno Medina-Noyola. 2007-12-13. First-principles Predictor of the Location of Ergodic-Non-ergodic Transitions. https://arxiv.org/abs/0712.2071

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