Investigation of phase separation within the generalized Lin–Taylor model for a binary liquid mixture of large hexagonal and small triangular particles

Abstract

The generalized Lin–Taylor model defined on the hexagonal lattice is used to investigate the phase separation in an asymmetric binary liquid mixture consisting of large A (hexagons) and small B (triangles) particles. By considering interaction energies between A–A and A–B pairs of particles that occupy nearest-neighbour cells of the hexagonal lattice, we have derived an exact solution for the considered model system having established a mapping correspondence with the two-dimensional Ising model on its dual triangular lattice. Altogether, six different types of coexistence curves including those with re-entrant miscibility regions (i.e. closed-loop coexistence curves) were found with dependence on the relative strength between both coupling constants.

Acknowledgements

J. Strecka would like to thank José Manuel Romero-Enrique and George Jackson for stimulating correspondence and for sending several relevant articles on the re-entrant phenomena cited in this work.

 The authors greatly acknowledge financial support of this work provided under the grant VEEA 1/2009/05.