INSTITUTO DE FISICA LA PLATA
Unidad Ejecutora - UE
congresos y reuniones científicas
Study of the magnetic and electronic properties of the Fe4N with pressure
A.V. GIL REBAZA, J. DESIMONI, E.L. PELTZER Y BLANCÁ
Conferencia; At the Frontiers of Condensed Matter; 2008
Fe4N displays a remarkably rich behavior that has attracted the attention of applied as well as basic researchers for as long as 80 years. The earliest interest in the synthesis and study of Fe4N was motivated by its possible application as a catalyst for the production of ammonia and for its role in the surface treatment of steels with ammonia. Later, its potential as a material for high-density magnetic recording was pointed out and was studied as a component in various thin film devices, due to its high magnetic flux density, low coercivity, low resistance and other suitable properties. This material, like many others, presents a variation of its magnetic properties to apply an external pressure, showing a magnetic structure that has not yet been fully explained. The Fe4N has anti-perovskite structure with two distinguishables Fe atoms, an atom occupy the corners of the cubic unit cell, FeI , and the other in the face center of cubic, FeII , while the N atoms is in the body center. In the present work, we report ab-initio studies about the magnetic properties variations of Fe4N under pressure where all calculates were performed using Full-Potential Linearised Augmented Plane Wave Method (FP-LAPW) and the exchange-correlation functional were treated using the Perdew-Burke-Ernzerhof functional and Generalized Gradient Approximation (PBE-GGA). Our results show that the magnetic moment of FeI is almost constant while the magnetic moment of FeII shows an almost discontinuous variation. This is expressed mainly in changing of the electronic structure and specifically in a peculiar behavior of Density of States (DOS), showing a compression of electronic states close to -3eV.