Anomalous temperature dependence of the first diffraction peak in vitreous boron trioxide

Abstract

11 págs.; 9 figs. ; The temperature dependence of the parameters characterizing the first peak in the S(Q) and S(Q,E=0) diffraction patterns of vitreous boron trioxide is considered in some detail. The analysis of the experimental spectra is aided by results derived from molecular-dynamics simulations, which enable us to isolate the most relevant features driving the variation with temperature of both structure factors. The relevance of the present results regarding some recent phenomenological approaches developed towards the understanding of the dynamics of glasses at intermediate temperatures is finally discussed. ©1996 American Physical Society ; Work was performed in part under D.G.I.C.Y.T (Spain) Grant No. PB92-0114-C03-01. Financial support from the Large Scale Facilities Programme of the European Union for the measurements carried at Risoe National Laboratory (Denmark) is acknowledged. J.D. wishes to thank CONICET (Argentina) and CSIC (Spain) for financial support. ; Peer Reviewed