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arXiv · 1805.06874

Structural properties of the Jagla fluid

Mariano López de Haro·Álvaro Rodríguez-Rivas·Santos B. Yuste·Andrés Santos
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Abstract

The structural properties of the Jagla fluid are studied by Monte Carlo (MC) simulations, numerical solutions of integral equation theories, and the (semi-analytical) rational-function approximation (RFA) method. In the latter case, the results are obtained from the assumption (supported by our MC simulations) that the Jagla potential and a potential with a hard core plus an appropriate piecewise constant function lead to practically the same cavity function. The predictions obtained for the radial distribution function, $g(r)$, from this approach are compared against MC simulations and integral equations for the Jagla model, and also for the limiting cases of the triangle-well potential and the ramp potential, with a general good agreement. The analytical form of the RFA in Laplace space allows us to describe the asymptotic behavior of $g(r)$ in a clean way and compare it with MC simulations for representative states with oscillatory or monotonic decay. The RFA predictions for the Fisher--Widom and Widom lines of the Jagla fluid are obtained.

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Mariano López de Haro, Álvaro Rodríguez-Rivas, Santos B. Yuste, Andrés Santos. 2018-07-31. Structural properties of the Jagla fluid. https://doi.org/10.1103/physreve.98.012138

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