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Quasi-saddles as relevant points of the potential energy surface in the dynamics of supercooled liquids

L. Angelani·R. Di Leonardo·G. Ruocco·A. Scala·F. Sciortino
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Abstract

The supercooled dynamics of a Lennard-Jones model liquid is numerically investigated studying relevant points of the potential energy surface, i.e. the minima of the square gradient of total potential energy $V$. The main findings are: ({\it i}) the number of negative curvatures $n$ of these sampled points appears to extrapolate to zero at the mode coupling critical temperature $T_c$; ({\it ii}) the temperature behavior of $n(T)$ has a close relationship with the temperature behavior of the diffusivity; ({\it iii}) the potential energy landscape shows an high regularity in the distances among the relevant points and in their energy location. Finally we discuss a model of the landscape, previously introduced by Madan and Keyes [J. Chem. Phys. {\bf 98}, 3342 (1993)], able to reproduce the previous findings.

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L. Angelani, R. Di Leonardo, G. Ruocco, A. Scala, F. Sciortino. 2002-03-14. Quasi-saddles as relevant points of the potential energy surface in the dynamics of supercooled liquids. https://doi.org/10.1063/1.1475764

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