Phase transition properties of Bell-Lavis model

TL;DR

This study uses Monte Carlo simulations to analyze phase transitions in the Bell-Lavis model, revealing universality classes and phase boundary behaviors, including first-order transitions and crossover phenomena.

Contribution

It provides a comprehensive analysis of the phase transition universality classes in the Bell-Lavis model across different chemical potentials, highlighting differences from similar models.

Findings

Transitions are in the three-state Potts universality class for most of the honeycomb phase.

First-order transitions occur at the phase boundary with the low-density gas.

Crossover from Potts to Ising universality class is observed at certain phase boundaries.

Abstract

Using Monte Carlo calculations we analyze the order and the universality class of phase transitions into a low density (honeycomb) phase of a triangular antiferromagnetic three-state Bell-Lavis model. The results are obtained in a whole interval of chemical potential $\mu$ corresponding to the honeycomb phase. Our results demonstrate that the phase transitions might be attributed to the three-state Potts universality class for all $\mu$ values except for the edges of the honeycomb phase existence. At the honeycomb phase and the low density gas phase boundary the transitions become of the first order. At another, honeycomb-to-frustrated phase boundary, we observe the approach to the crossover from the three-state Potts to the Ising model universality class. We also obtain the Schottky anomaly in the specific heat close to this edge. We show that the intermediate planar phase, found in a very similar antiferromagnetic triangular Blume-Capel model, does not occur in the Bell-Lavis model.