Nonlinear structural relaxation model for the glassy state-application to B sub 2 O sub 3

Traditionally, fictive temp. has been used to characterize the structural state of glasses. Since this concept has shortcomings, use of a second thermodynamic ordering parameter along with fictive temp. in a nonlinear model is proposed. This model is applied to refractive index relaxation data, from the literature, for B sub 2 O sub 3 glass. Data were considered as the refractive index relaxed to a new equilibrium temp. from both higher and lower fictive temps. 25 refs.