The liquid-glass transition in a strong network glass former investigated by neutron scattering

The temperature dependence of the non-ergodicity parameter of a strong glas s former, B2O3, has been investigated using neutron scattering. A clear cha nge is observed at a temperature (similar to 800 K) well above the g-lass-t ransition temperature (similar to 523 K), and a complementary behaviour is observed for the strength of a fast relaxation process. The results directl y shows the existence of a dynamic transition in the super-cooled melt of a strong network glass former. The transition, which is corroborated by the analysis of sound velocity and viscosity data, resembles that predicted by the mode coupling theory, and thereby shows the applicability of this theor y even to strong glass formers.