Phase diagram of Pb(Zr,Ti)O3 solid solutions from first principles

TL;DR

This study develops a first-principles-derived computational scheme to analyze the finite-temperature phase diagram of Pb(Zr,Ti)O3 solid solutions, resolving existing controversies and predicting new phases supported by neutron diffraction data.

Contribution

A novel numerical approach incorporating multiple degrees of freedom to accurately predict phase behavior in Pb(Zr,Ti)O3 near the morphotropic phase boundary.

Findings

Resolved the monoclinic ground-state controversy for some Ti compositions.

Discovered an overlooked phase in the phase diagram.

Identified three multiphase points with four phases each.

Abstract

A first-principles-derived scheme, that incorporates ferroelectric and antiferrodistortive degrees of freedom, is developed to study finite-temperature properties of PbZr1-xTixO3 solid solutions near its morphotropic phase boundary. The use of this numerical technique (i) resolves controversies about the monoclinic ground-state for some Ti compositions, (ii) leads to the discovery of an overlooked phase, and (iii) yields three multiphase points, that are each associated with four phases. Additional neutron diffraction measurements strongly support some of these predictions.