Revisiting the Common Neighbour Analysis and the Centrosymmetry Parameter

TL;DR

This paper reviews and improves two widely used methods for structural classification in crystalline simulations, enhancing their robustness and interpretability through proposed modifications.

Contribution

It introduces modified variants of Common Neighbour Analysis and Centrosymmetry Parameter that address their failure modes and biases.

Findings

Modified methods show improved robustness.

Enhanced interpretability of structural classification.

Broader applicability in crystalline simulations.

Abstract

We review two standard methods for structural classification in simulations of crystalline phases, the Common Neighbour Analysis and the Centrosymmetry Parameter. We explore the definitions and implementations of each of their common variants, and investigate their respective failure modes and classification biases. Simple modifications to both methods are proposed, which improve their robustness, interpretability, and applicability. We denote these variants the Interval Common Neighbour Analysis, and the Minimum-Weight Matching Centrosymmetry Parameter.