Grain boundary relaxation and reconstruction: effect on local magnetic moment

TL;DR

This study investigates how different types of grain boundary relaxation and reconstruction in bcc-iron influence local magnetic moments, revealing that reconstruction causes non-uniform magnetic distribution.

Contribution

It provides a detailed numerical analysis of the relationship between grain boundary relaxation types and local magnetic properties in bcc-iron using first principles calculations.

Findings

Reconstruction leads to non-uniform magnetic moments.

Simple relaxation results in uniform magnetic distribution.

Optimized atomic configurations were achieved via simulated annealing and genetic algorithms.

Abstract

We present a detailed numerical study on structure and local magnetic properties of $\langle 100 \rangle$ symmetric tilt grain boundaries in bcc-iron. Particular attention is paid to connection between type of grain boundary relaxation and local magnetic properties. Results from first principles calculation showed that grain boundary reconstruction leads to non-uniform distribution of local magnetic moments in grain boundary plane. This is in contrast with the result obtained in grain boundary plane, where simple relaxation is observed. Well optimized atomic configurations in the vicinity of the interface were achieved by simulated annealing optimization technique improved by combination with genetic algorithm.