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Nematic and gas-liquid transitions for sticky rods on square and cubic lattices

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 نشر من قبل Miriam Klopotek
 تاريخ النشر 2019
  مجال البحث فيزياء
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Using grand-canonical Monte Carlo simulations, we investigate the phase diagram of hard rods of length $L$ with additional contact (sticky) attractions on square and cubic lattices. The phase diagram shows a competition between gas-liquid and ordering transitions (which are of demixing type on the square lattice for $L ge 7$ and of nematic type on the cubic lattice for $L ge 5$). On the square lattice, increasing attractions initially lead to a stabilization of the isotropic phase. On the cubic lattice, the nematic transition remains of weak first order upon increasing the attractions. In the vicinity of the gas-liquid transition, the coexistence gap of the nematic transition quickly widens. These features are different from nematic transitions in the continuum.

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