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Temperature Expansions in the Square Shoulder Fluid II: Thermodynamics

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 Added by Olivier Coquand
 Publication date 2019
  fields Physics
and research's language is English




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In a companion paper, we derived analytical expressions for the structure factor of the square-shoulder potential in a perturbative way around the high- and low-temperature regimes. Here, various physical properties of these solutions are derived. In particular, we investigate the large wave number sector, and relate it to the contact values of the pair-correlation function. Then, thermoelastic properties of the square-shoulder fluids are discussed.



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70 - O. Coquand , M. Sperl 2019
We investigate the spatial structure of dense square-shoulder fluids. To this end we derive analytical perturbative solutions of the Ornstein-Zernike equation in the low- and high-temperature limits as expansions around the known hard sphere solutions. We then discuss the suitability of perturbative approaches in relation to the Ornstein-Zernike equation.
This paper continues the investigation of the exponentially repulsive EXP pair-potential system of Paper I with a focus on isomorphs in the low-temperature gas and liquid phases. As expected from the EXP systems strong virial potential-energy correlations, the systems reduced-unit structure and dynamics are isomorph invariant to a good approximation. Three methods for generating isomorphs are compared: the small-step method that is exact in the limit of small density changes and t
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