8th Liquid Matter Conference September 6-10, 2011 Wien, Austria ...

P8.12Thu 811:10-14:00Time resolved high energy x-ray diffraction study of thestructure of supercooled calcium aluminosilicate liquidsJames W E Drewitt, 1 Aleksei Bytchkov, 2 Jad Kozaily, 3 Viviana Cristiglio, 3 Henry EFischer, 3 Sandro Jahn, 4 Noël Jakse, 5 Alain Pasturel, 5 and Louis Hennet 11 CNRS - CEMHTI, 1D avenue de la Recherche Scientifique, 45071, ORLEANS,France2 European Synchrotron Radiation Facility (ESRF), Grenoble, France3 Institut Laue Langevin (ILL), Grenoble, France4 GFZ, Potsdam, Germany5 SIMAP, SAINT-MARTIN D’HERES, FranceMelts in the CaO-Al 2 O 3 system are classified as ”fragile” liquids, whereby dynamical properties,such as viscosity, exhibit a marked deviation from Arrhenius behaviour. The introduction of lowconcentrations of SiO 2 , an archetypal ”strong” network glass former, into the CaO-Al 2 O 3 systemreduces the fragility and strongly affects some of the glass forming properties of these melts. Recentadvances in detector technology at synchrotron radiation facilities and the development oflaser heated aerodynamic levitation devices enable the possibility of in situ diffraction measurementswith ms time resolution to follow the structural evolution of glass forming liquids as theyare supercooled through the glass transition into the glassy state. In this study we report time resolvedhigh energy x-ray diffraction measurements of supercooled (CaAl 2 O 4 ) 1−x (SiO 2 ) x liquidswith x = 0, 0.12, 0.19, 0.33. We discuss the structural modifications that occur with the additionof SiO 2 into the CaAl 2 O 4 system and the changes in structure experienced during glass formation.The interpretation of the total structure factor measurements will be aided by complimentarymolecular dynamics computer simulations of the high temperature liquid, supercooled and glassystates.12