Direct dipole induced energy transfer: A microscopic model for glass relaxation

摘要

A microscopic model for glass relaxation phenomena is presented based on direct energy transfer from lsquo;lsquo;tightrsquo;rsquo; donor sites to lsquo;lsquo;loosersquo;rsquo; acceptor sites. The rate of energy transfer, induced by the stress energy field from the donorW, is proportional to 1/R6. Summing over donor sites with different acceptor environments, gives the Williamsndash;Watt form for relaxation vs time with bgr;=0.5. More generally, bgr; is the dimensionality of the structure divided by the order of the donorndash;acceptor energy transfer mechanism and thermorheological simplicity follows from one relaxation mechanism. Other properties of glass relaxation phenomena including the temperature and fictive temperature dependence of relaxation times are readily understood.