1 Structure of interacting aggregates of silica nanoparticles in a polymer matrix: Small-angle scattering and Reverse Monte-Carlo simulations Julian Oberdisse 1 , Peter Hine 2 and Wim Pyckhout-Hintzen 3 1 Laboratoire des Colloïdes, Verres et Nanomatériaux, UMR 5587 CNRS,Université Montpellier II, 34095 Montpellier, France 2 IRC in Polymer Science and Technology , School of Physics and Astronomy University of Leeds, Leeds, LS2 9JT, United Kingdom 3 Institut für Festkörperforschung, FZ Jülich, 52425 Juelich, Germany 13 th of October 2006 Figures : 10 Tables : 3