Hydrogen induced AFM to FM magnetic transition in ε-FeHx

León, Andrea; Velasquez, EA; Francisco J Torres; J. Mejia-Lopez; P. Vargas

Keywords: Magnetic Materials, Phase transitions, Hydrogen

Abstract

We study the magnetic behavior of the metallic system∊-FeH x as a function hydrogen concentration (x). Using ab-initio density functional theory, we investigate the effect of hydrogen on the stability of magnetic configurations considering two antiferromagnetic (AFM) phases and a ferromagnetic (FM) one present in∊-Fe (AFM-I and AFM-II). Our results show a magnetic transition induced by H between AFM and FM around x= 0.44. In this way, two main effects can determine the stability and the magnetic phase transition: a volume increase that produces an AFM to FM transition and the charge transfer effect from H to Fe energetically favors the FM phase. We discuss these behaviors in detail and physically explain the magnetic transition and the overall behavior using a phenomenological Stoner model for these systems.

Más información

Título de la Revista: JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
Volumen: 498
Editorial: Elsevier
Fecha de publicación: 2020
Idioma: English
DOI:

https://doi.org/10.1016/j.jmmm.2019.166147

Notas: ISI/SCOPUS Quartile Q2