An analysis of the short and intermediate range order in several organic glass-forming liquids from the static structure factor under pressure

We report elastic neutron scattering experiments on several molecular glass-forming liquids (toluene, m-toluidine, m-fluoroaniline) as well as a polymer (polybutadiene, M = 8000). The pressure dependence of the static structure factor is analyzed in the region of wave vectors associated with short and intermediate range order ORO). In all cases, the short range order (SRO) varies essentially with density. For m-fluoroaniline land m-toluidine not presented here), a prepeak appears at low wave vectors corresponding to some 'IRO' which is strongly temperature dependent. (C) 1998 Elsevier Science B.V. All rights reserved.