A cavitation transition in the energy landscape of simple cohesive liquids and glasses

作者：Altabet Y Elia; Stillinger Frank H; Debenedetti Pablo G^*

来源：Journal of Chemical Physics, 2016, 145(21): 211905.

DOI：10.1063/1.4959846

In particle systems with cohesive interactions, the pressure-density relationship of the mechanically stable inherent structures sampled along a liquid isotherm (i.e., the equation of state of an energy landscape) will display a minimum at the Sastry density rho S. The tensile limit at rho S is due to cavitation that occurs upon energy minimization, and previous characterizations of this behavior suggested that rho S is a spinodal-like limit that separates all homogeneous and fractured inherent structures. Here, we revisit the phenomenology of Sastry behavior and find that it is subject to considerable finite-size effects, and the development of the inherent structure equation of state with system size is consistent with the finite-size rounding of an athermal phase transition. What appears to be a continuous spinodal-like point at finite system sizes becomes discontinuous in the thermodynamic limit, indicating behavior akin to a phase transition. We also study cavitation in glassy packings subjected to athermal expansion. Many individual expansion trajectories averaged together produce a smooth equation of state, which we find also exhibits features of finite-size rounding, and the examples studied in this work give rise to a larger limiting tension than for the corresponding landscape equation of state. Published by AIP Publishing.

• 出版日期2016-12-21