Inherent Structure Approach to the Study of Glass Forming Liquids: Onset temperature of slow dynamics and fragility
Abstract
Dynamic and thermodynamic aspects of glass forming liquids have recently been studied extensively through the analysis of their potential energy landscape; in particular, the analysis of the statistics and properties of local energy minima, or inherent structures, has been employed in studying various aspects of glass forming liquids, such as the onset of slow dynamics, thermodynamic aspects of fragility, crossover to energy landscape dominated dynamics near the mode coupling temperature, the glass transition and aging dynamics at low temperatures. One part of this presentation will be devoted to the thermodynamic analysis of fragility. In previous work, a thermodynamic expression for fragility has been obtained, which relies on the applicability of the Adam-Gibbs relation and relates parameters describing the energy landscape of a liquid to its fragility. Recent work addressing some open questions concerning such analysis will be described, including analysis of other model systems than previously studied. The other question that will be addressed is the onset of slow dynamics and its relation to changes in the energy landscape sampled by the liquid. Although empirical observations clearly demonstrate a change in the sampled energy landscape across the onset temperature, a clear understanding, including its relationship to structural change and heterogeneous dynamics, is lacking. Results from recent analysis of behaviour near the onset temperature will be presented.
- Publication:
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APS March Meeting Abstracts
- Pub Date:
- March 2004
- Bibcode:
- 2004APS..MARS35007S