Amorphous ground states and collective dynamics in a 2D glass-forming mixture

On cooling, many supercooled liquids arrive at a rigid disordered state, metastable to the crystal. In this paper, we characterize such amorphous ground states in a binary mixture of soft discs in 2D using molecular dynamics simulations. We find these ground states exhibit very strong correlations between local fivefold and sevenfold sites and an inherent stress heterogeneity The heat capacity C-p is found to undergo an abrupt increase on heating through a glass transition temperature. We show that this increase is largely due to volume fluctuations.