Alladi Ramakrishnan Hall

Cooperativity and dynamics of glass-forming liquids

Ankit Singh

BHU, Varanasi

We have developed a theory to calculate the structural relaxation time of supercooled liquids. Using information of the configurational entropy and structure, we calculate the number of particles in different dynamical states. We propose a categorization of particles within a supercooled liquid into three distinct categories based on their behavior: free particles, trapped or localized particles, and intermittent particles. The concentration of these particles can be determined using the pair correlation function and bath fluctuation. Clusters formed by localized particles are identified as cooperative regions of relaxation, where cooperativity is defined by the number of particles within the cluster bonded with the central particle. The effective activation energy characterizes the energy required for the irreversible rearrangement of these clusters, while the relaxation time is derived from the Arrhenius law. The presented results encompass athermal and thermal systems, providing insights into the dynamics of particles in supercooled liquids and their relaxation behavior.