Order Parameter Engineering for Random Systems

TL;DR

This paper introduces the OPERA scheme, a high-throughput method for quantifying chemical short-range order in multicomponent crystalline materials, addressing limitations of existing parameters and applicable to various alloy and oxide systems.

Contribution

The paper proposes the $ ext{ extDelta}$-parameter and OPERA framework for efficient, high-throughput analysis of chemical short-range order in multicomponent systems, improving upon Warren-Cowley measures.

Findings

$ ext{ extDelta}$-parameter effectively describes CSRO in alloys and oxides.

OPERA framework works for both semi-canonical and canonical ensembles.

The method outperforms traditional order parameters in capturing chemical order.

Abstract

The chemical short-range order (CSRO) in the crystalline materials influences the properties and its effect is particularly important in the context of the multicomponent materials. We propose a scheme for CSRO parameter or $\mathrm{\Delta-}$parameter in terms of number of like and unlike bonds in the multicomponent systems. The OPERA or $\bf{O}$rder $\bf{P}$arameter $\bf{E}$ngineering for $\bf{RA}$ndom Systems scheme for both semi-canonical as well as canonical ensemble is proposed. The proposed framework provides a high-throughput scheme for exploration of the CSRO in terms of the $\mathrm{\Delta-}$parameter. We demonstrate the applicability of the $\mathrm{\Delta-}$parameter for describing the CSRO in multicomponent alloys and oxides (FCC-CoCrNi, BCC-MoNbTaW and (CoCuMgNiZn)O). We show that the $\mathrm{\Delta-}$parameter not only inherits the merit of Warren-Cowley order parameter, but it also addresses its limitations. The $\mathrm{\Delta-}$parameter being a scalar quantity can represent the chemical order and OPERA framework can deal with both semi-canonical and canonical ensemble