Potential energy landscape of simple structural glasses

We numerically investigate the "topography" of the multidimensional potential energy landscape of Lennard-Jones model glasses of small size. We first determine the statistical features of local minima and saddle points, relationships betwenn them and cross-correlations among the measured quatities. From these informations we approximate the partition function of the glass restricting the sum over potential energy minima and taking into account harmonic vibrations around them. The approximation is validated by the comparison with Molecular Dynamics computation up to a temperature in the liquid phase, evidencing the reliability of simple local-vibrations/collective-jumps model in describing glass-forming systems.