Liquid-Liquid Immiscibility in Pure Fluids: Polyamorphism in Simulations of a Network-Forming Fluid

C. J. Roberts; A. Z. Panagiotopoulos; Pablo G. Debenedetti

doi:10.1103/PhysRevLett.77.4386

Liquid-Liquid Immiscibility in Pure Fluids: Polyamorphism in Simulations of a Network-Forming Fluid

C. J. Roberts, A. Z. Panagiotopoulos, and Pablo G. Debenedetti

Phys. Rev. Lett. 77, 4386 – Published 18 November 1996

Abstract

We report Monte Carlo simulations that show both vapor-liquid and closed-loop liquid-liquid equilibrium in a pure substance, for a model fluid that forms orientation-dependent intermolecular bonds. This is the first time that direct evidence of liquid-liquid immiscibility in a pure fluid has been found using exact methods. Because the model is formulated in terms of a tetrahedrally coordinated molecule, the results are relevant to a broad class of substances, particularly to the transitions between amorphous phases which are known to occur in $H_{2} O$ , ${SiO}_{2}$ , and ${GeO}_{2}$ .

Received 9 September 1996

DOI:https://doi.org/10.1103/PhysRevLett.77.4386

Authors & Affiliations

C. J. Roberts¹, A. Z. Panagiotopoulos², and Pablo G. Debenedetti¹

¹Department of Chemical Engineering, Princeton University, Princeton, New Jersey, 08544
²Department of Chemical Engineering, Cornell University, Ithaca, New York, 14853