Magnetic structure of the magnetocaloric compound AlFe2B2

TL;DR

This study investigates the crystal and magnetic structures of AlFe2B2, revealing its ferromagnetic order at 285 K and its magnetocaloric properties, combining experimental diffraction, magnetization measurements, and electronic structure calculations.

Contribution

It provides detailed structural and magnetic characterization of AlFe2B2, including its ferromagnetic transition and magnetocaloric effect, using combined experimental and computational methods.

Findings

Crystallizes in orthorhombic Cmmm structure

Ferromagnetic order at 285 K

Magnetic entropy change of -1.3 J/K kg at transition

Abstract

The crystal and magnetic structures of AlFe2B2 have been studied with a combination of X-ray and neutron diffraction and electronic structure calculations. The magnetic and magnetocaloric properties have been investigated by magnetisation measurements. The samples have been produced using high temperature synthesis and subsequent heat treatments. The compound crystallises in the orthorhombic crystal system Cmmm and it orders ferromagnetically at 285 K through a second order phase transition. At temperatures below the magnetic transition the magnetic moments align along the crystallographic $a$-axis. The magnetic entropy change from 0 to 800 kA/m was found to be -1.3 J/K kg at the magnetic transition temperature.