Potential energy landscape signatures of slow dynamics in glass forming liquids

We study the properties of local potential energy minima (`inherent structures') sampled by liquids at low temperatures as an approach to elucidating the mechanisms of the observed dynamical slowing down observed as the glass transition temperature is approached. This onset of slow dynamics is accompanied by the sampling of progressively deeper potential energy minima. Further, evidence is found in support of a qualitative change in the inherent structures sampled in a temperature range that includes the mode coupling critical temperature T_c, such that a separation of vibrational relaxation within inherent structure basins from that due to inter-basin transitions becomes valid at temperatures T<T_c. Average inherent structure energies do not show any qualitatively significant system size dependence.