Testing “microscopic” theories of glass-forming liquids
Laboratoire Charles Coulomb, CNRS-UMR 5221, Université Montpellier 2, Place Eugène Bataillon, 34095, Montpellier Cedex, France
2 LPTMC, CNRS-UMR 7600, Université Pierre et Marie Curie, 4 Pl. Jussieu, boîte 121, 75252, Paris Cedex 05, France
Revised: 15 July 2011
Accepted: 20 July 2011
Published online: 23 September 2011
We assess the validity of “microscopic” approaches of glass-forming liquids based on the sole knowledge of the static pair density correlations. To do so, we apply them to a benchmark provided by two liquid models that share very similar static pair density correlation functions while displaying distinct temperature evolutions of their relaxation times. We find that the approaches are unsuccessful in describing the difference in the dynamical behavior of the two models. Our study is not exhaustive, and we have not tested the effect of adding corrections by including, for instance, three-body density correlations. Yet, our results appear strong enough to challenge the claim that the slowdown of relaxation in glass-forming liquids, for which it is well established that the changes of the static structure factor with temperature are small, can be explained by “microscopic” approaches only requiring the static pair density correlations as nontrivial input.
© EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg, 2011