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Mode-coupling theory predictions for a limited valency attractive square-well model

E. Zaccarelli·I. Saika-Voivod·A. J. Moreno·E. La Nave·S. V. Buldyrev·F. Sciortino·P. Tartaglia
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Abstract

Recently we have studied, using numerical simulations, a limited valency model, i.e. an attractive square well model with a constraint on the maximum number of bonded neighbors. Studying a large region of temperatures $T$ and packing fractions $ϕ$, we have estimated the location of the liquid-gas phase separation spinodal and the loci of dynamic arrest, where the system is trapped in a disordered non-ergodic state. Two distinct arrest lines for the system are present in the system: a {\it (repulsive) glass} line at high packing fraction, and a {\it gel} line at low $ϕ$ and $T$. The former is essentially vertical ($ϕ$-controlled), while the latter is rather horizontal ($T$-controlled) in the $(ϕ-T)$ plane. We here complement the molecular dynamics results with mode coupling theory calculations, using the numerical structure factors as input. We find that the theory predicts a repulsive glass line -- in satisfactory agreement with the simulation results -- and an attractive glass line which appears to be unrelated to the gel line.

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E. Zaccarelli, I. Saika-Voivod, A. J. Moreno, E. La Nave, S. V. Buldyrev, F. Sciortino, P. Tartaglia. 2006-05-08. Mode-coupling theory predictions for a limited valency attractive square-well model. https://doi.org/10.1088/0953-8984%2F18%2F36%2Fs11

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