Thermodynamics and aging in supercooled liquids: the energy landscape approach

We summarize some of the relevant information obtained from the study of the potential energy surface in the multidimensional configurational space sampled by a model supercooled liquid. Using the energy landscape approach we study both the equilibrium and the aging regimes of a prototypical binary Lennard–Jones liquid and, in both cases, we evaluate the relevant temperatures which characterize the system. From the theoretical point of view we introduce an expression for the free energy of the system which we show to be valid both in equilibrium and quasi-equilibrium aging situations.