Evaluation of the "disorder temperature" and "free volume" formalisms   via simulations of shear banding in amorphous solids
  Molecular dynamics simulations of shear band development over 1000% strain in simple shear are used to test whether the local plastic strain rate is proportional to exp(-1/chi), where chi is a dimensionless quantity related to the "disorder temperature" or "free volume" that characterizes the structural state of the glass. Scaling is observed under the assumption that chi is linearly related to the local potential energy per atom. This analysis permits the extraction of the potential energy per atom at which chi=0 and the approximate energy needed to create a shear transformation zone. 
Yunfeng Shi, Michael B. Katz, Hui Li and Michael L. Falk