DFT STUDY OF ELECTRONIC STRUCTURE AND MAGNETIC AND HYPERFINE PROPERTIES OF Fe2AlO4 AND FeAl2O4

K. L. SALCEDO RODRÍGUEZ; J. J. MELO QUINTERO; C. RODRIGUEZ TORRES; L. A. ERRICO

Cartagena

Conferencia; XXXVII International Conference on the applications of the Mossbauer effect (XXXVII ICAME); 2023

In the last years the modelling of materials in the framework of the Density functional theory (DFT) has allowed a deeper understanding of structural, electronic, magnetic, optical and transport properties (among other) of different kind of materials. Moreover, the combination DFT-experimental results raise the possibility to correlate fine details of the electronic structure of a given system with its physical properties, favouring the design of functional materials [1, 2]. Among the oxide universe, spinel oxides have received considerable attention from both experimental and theoretical sides due to their intriguing electronic and magnetic properties and technological importance. Fe-Al spinel oxides are compounds of great interest in areas such as geology and mineralogy and, due to the sensibility of the physical properties of these systems on the synthesis process. In this work, the structural, electronic, magnetic, and hyperfine properties of two Fe-Al spinel oxides, namely FeAl2O4 (hercynite) and Fe2AlO4 (Al-ferrite) were studied by means of Density Functional Theory (DFT)-based first principles calculations. To determine the structural and magnetic equilibrium structures of both oxides, different cationic inversion degrees, magnetic configurations and distributions were considered for Fe and Al ions in the octahedral and tetrahedral sites of the spinel structures. Calculations confirmed the preference of the Al ions to occupy the octahedral cationic sites and predicted that both Fe-Al spinel oxides present a semiconductor nature. By comparing the predictions for the hyperfine parameters at the Fe sites with the experimental results obtained in the Mossbauer experiments, the validity of the proposed structural and magnetic structure of FeAl2O4 was confirmed. Finally, a discussion is made to compare the results of this study with the Mossbauer results reported in the literature for Fe2AlO4[3]. References[1] C.E. Rodriguez Torres, J.J. Melo Quintero, L.A. Errico, Ab initio calculation ofstructural, electronic, and magnetic properties and hyperfine parameters at the Fesites of pristine ZnFe2O4, J. Alloy. Comp. 74 (2018) 746.[2] H. Stepankova, P. Novak, J. Zukrowski, A. Kozlowski, Z. Kakol, Z. Tarnawski, R.Reznicek, V. Chlan, J.M. Honig, Understanding the Mossbauer spectrum ofexperiment, Phys. Rev. B 96 (2017) 95124.[3] K.L. Salcedo Rodriguez, J.J. Melo Quintero, C.E. Rodriguez Torres, and L. Errico, Structural, electronic,magnetic and hyperfine properties of Fe2AlO4 and FeAl2O4. A DFT study, Journal of Alloys andCompounds, Volume 958, 5 (2023) 170385