**Uhlenbeck-Ford model: Phase diagram and corresponding-states analysis**

RP Leite and PA Santos-Florez and M de Koning, PHYSICAL REVIEW E, 96, 032115 (2017).

DOI: 10.1103/PhysRevE.96.032115

Using molecular dynamics simulations and nonequilibrium thermodynamic-
integration techniques we compute the Helmholtz free energies of the
body-centered-cubic (bcc), face-centered-cubic (fcc), hexagonal close-
packed, and fluid phases of the Uhlenbeck-Ford model (UFM) and use the
results to construct its phase diagram. The pair interaction associated
with the UFM is characterized by an ultrasoft, purely repulsive pair
potential that diverges logarithmically at the origin. We find that the
bcc and fcc are the only thermodynamically stable crystalline phases in
the phase diagram. Furthermore, we report the existence of two reentrant
transition sequences as a function of the number density, one featuring
a fluid-bcc-fluid succession and another displaying a bcc-fcc-bcc
sequence near the triple point. We find strong resemblances to the phase
behavior of other soft, purely repulsive systems such as the Gaussian-
core model (GCM), inverse-power-law, and Yukawa potentials. In
particular, we find that the fcc-bcc-fluid triple point and the phase
boundaries in its vicinity are in good agreement with the prediction
supplied by a recently proposed corresponding-states principle **J. Chem.
Phys. 134, 241101 (2011); Europhys. Lett. 100, 66004 (2012)**. The
particularly strong resemblance between the behavior of the UFM and GCM
models are also discussed.

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