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Free Energy Landscape Of Simple Liquids Near The Glass Transition

Chandan Dasgupta·Oriol T. Valls
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Abstract

Properties of the free energy landscape in phase space of a dense hard sphere system characterized by a discretized free energy functional of the Ramakrishnan-Yussouff form are investigated numerically. A considerable number of glassy local minima of the free energy are located and the distribution of an appropriately defined ``overlap'' between minima is calculated. The process of transition from the basin of attraction of a minimum to that of another one is studied using a new ``microcanonical'' Monte Carlo procedure, leading to a determination of the effective height of free energy barriers that separate different glassy minima. The general appearance of the free energy landscape resembles that of a putting green: deep minima separated by a fairly flat structure. The growth of the effective free-energy barriers with increasing density is consistent with the Vogel-Fulcher law, and this growth is primarily driven by an entropic mechanism.

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Chandan Dasgupta, Oriol T. Valls. 2000-02-06. Free Energy Landscape Of Simple Liquids Near The Glass Transition. https://doi.org/10.1088/0953-8984%2F12%2F29%2F327

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