IBERMÖSS-2019, Bilbao, 30-31 may 2019. --https://www.ehu.eus/es/web/ibermossmeetingStrontium ferrite (SFO, SrFe12O19) is a ferrite
employed for permanent magnets due to its high
magnetocrystalline anisotropy. Since its discovery
in the mid-20th century, this hexagonal ferrite has
become an increasingly important material both
commercially and technologically, finding a variety
of uses and applications. Its structure can be
considered a sequence of alternating spinel (S) and
rocksalt (R) blocks. All the iron cations are in the
Fe3+ oxidation state and it has a ferrimagnetic
configuration with five different cationic
environments for the iron (three octahedral sites, a
tetraedrical site and a bipiramidal site)[1,2].
We have studied the properties of SrFe 12O19 in the
shape of platelets, up to several micrometers in
width, and tens of nanometers thick, synthesized by
a hydrothermal method. We have characterized the
structural and magnetic properties of these platelets
by Mössbauer spectroscopy, x-ray transmission
microscopy (TMX), transmission electron
microscopy (TEM), x-ray diffraction (XRD),
vibrating-sample magnetometry (VSM), x-ray
absorption spectroscopy (XAS), x-ray circular
magnetic dichroism (XMCD) and photoemission
electron microscopy (PEEM). To the best of our
knowledge this is the first time that the x-ray
absorption spectra at the Fe L 2,3 edges of this
material in its pure form have been reported. The
Mössbauer results recorded from these platelets
both in the electron detection and transmission
modes have helped to understand the iron magnetic
moments determined by XMCD (Fig.1). The
experimental results have been complemented with
multiplet calculations aimed at reproducing the
observed XAS and XMCD spectra at the Fe L 2,3
absorption edge, and by density functional theory
(DFT) calculations to reproduce the oxygen K-
absorption edge. Finally the domain pattern
measured in remanence is in good agreement with
micromagnetic simulations [3]
