A Numerical Study of Phase Transitions Inside the Pores of Aerogels

Katarina Uzelac; Anwar Hasmy; Rémi Jullien

doi:10.1016/0022-3093(95)00078-x

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A Numerical Study of Phase Transitions Inside the Pores of Aerogels

Katarina Uzelac·Anwar Hasmy·Rémi Jullien

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Abstract

Phase transitions inside the pores of an aerogel are investigated by modelizing the aerogel structure by diffusion-limited cluster-cluster aggregation on a cubic lattice in a finite box and considering $q$-states Potts variables on the empty sites interacting via nearest-neighbours. Using a finite size scaling analysing of Monte-Carlo numerical results, it is concluded that for $q=4$ the transition changes from first order to second order as the aerogel concentration (density) increases. Comparison is made with the case $q=3$ (where the first order transition is weaker in three dimensions) and with the case $q=4$ but for randomly (non correlated) occupied sites. Possible applications to experiments are discussed.

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Katarina Uzelac, Anwar Hasmy, Rémi Jullien. 1995-04-13. A Numerical Study of Phase Transitions Inside the Pores of Aerogels. https://doi.org/10.1016/0022-3093(95)00078-x

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