Percolation model for structural phase transitions in Li$_{1-x}$H$_x$IO$_3$ mixed crystals

TL;DR

This paper introduces a percolation model to explain structural phase transitions in Li$_{1-x}$H$_x$IO$_3$ crystals, linking vacancy and hydrogen bond percolation to observed phase behavior.

Contribution

The study develops a percolation-based theoretical framework to understand phase transitions in mixed crystals, supported by Monte Carlo simulations of lattice occupancy.

Findings

Percolation thresholds align with experimental phase transition range

Lithium vacancies and hydrogen bonds drive the phase transition

Monte Carlo simulations validate the percolation model

Abstract

A percolation model is proposed to explain the structural phase transitions found in Li$_{1-x}$H$_x$IO$_3$ mixed crystals as a function of the concentration parameter $x$. The percolation thresholds are obtained from Monte Carlo simulations on the specific lattices occupied by lithium atoms and hydrogen bonds. The theoretical results strongly suggest that percolating lithium vacancies and hydrogen bonds are indeed responsible for the solid solution observed in the experimental range $0.22 < x < 0.36$.