Paeng Lab

In understanding amorphous materials, the dynamics of the material in the vicinity of the glass transition are essential since the glass transition determines the integrity of the materials as it is the process of forming an amorphous solid. Furthermore, unlike thermodynamic transitions like crystallization which is process of forming a crystalline solid, the glass transition is a purely kinetic process where the dramatic slowdown of molecular motion causes vitrification without any distinct structural changes. Consequently, the glassy state can be viewed as solid with a liquid structure and vice versa. The key dynamic features associated with glass transition are 1) the dramatic slowing of molecular motions upon cooling, which is also referred to as non-Arrhenius temperature dependence and the origin of glass formation, and 2) non-exponential relaxation of the dynamics which result from local dynamic heterogeneity of the system. In addition, these dynamic features are believed to be closely linked to other dynamics abnormalities such as Debye–Stokes–Einstein breakdown in such systems.