2003/03/25 by Masaki Sasai
Chemistry · Materials Science · Physics and Astronomy · #Advanced Physical and Chemical Molecular Interactions #Dissipation #Energy (signal processing) #Energy landscape #Fragility #Kinetic energy #Material Dynamics and Properties #Potential energy #Saddle point #Supercooling #Theoretical and Computational Physics #cond-mat.dis-nn #cond-mat.soft
paper · pdf · doi:10.1063/1.1574781
to appear in J. Chem. Phys
arxiv created 2003/03/25 · openalex publication_date 2003/05/29 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The thermodynamic and kinetic anomalies of supercooled liquids are analyzed from the perspective of energy landscapes. A mean-field model, a generalized random energy model of liquids, is developed which exhibits a dynamical transition of the onset of slow dynamics at T0, alteration of the nature of motion from saddle-to-saddle to minimum-to-minimum motion at Tc, and an ideal glass transition at Tk. If the energy spectrum of the configurations has a low energy tail, the model also allows a thermodynamic liquid–liquid transition at Tl. The liquid–liquid transition of the model is correlated to the kinetic fragile–strong transition accompanied by the anomalous slowing down of motion. Fragility of the system is classified in terms of features of the energy landscape such as ruggedness of the potential energy surface, size of the cooperative motion invoked in transition from one configuration to another, and energy needed to deform the local structure in the cooperative motion. A simple relation is found between diffusion constant, D and the saddle index of the potential energy surface, f as D∝fa, where a depends on the size of the cooperative motion.