Viscosity data for supercooled liquids are reexamined in terms of the random-potential model with use of the concept developed for treatment of electronic transport in random media with energetic disorder. η(T) is found to obey the predicted exp[(${\mathrm{T}}_0$/T${)}^2$] law covering 10 decades in η and extending to the glass transition which is considered to be a kinetic localization phenomenon. The crucial system paramter is the width σ of the (Gaussian) distribution of states which determines both the glass transition temperature and the T dependence of η via the characteristic temperature ${\mathrm{T}}_0$∝σ.

• Received 9 September 1986

DOI:https://doi.org/10.1103/PhysRevLett.58.767