Regensburg 2016 – wissenschaftliches Programm

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TT: Fachverband Tiefe Temperaturen

TT 77: Multiferroics
(Joint session of MA, DF, DS, KR and TT organized by MA)

TT 77.7: Vortrag

Donnerstag, 10. März 2016, 16:45–17:00, H34

First-principles calculations on anion doped GaFeO3 — •Jacqueline Atanelov and Peter Mohn — Technische Universität Wien, Institut für Angewandte Physik, Computational Materials Science

We present ab initio DFT calculations performed on stoichiometric and anion doped GaFeO3 substituting O by a C, N and S atom, respectively. Stoichiometric GaFeO3 has an antiferromagnetic (AFM) ground state. The Fe atoms of the sublattices Fe1 and Fe2 couple antiferromagnetically via the O atoms through the superexchange mechanism. Exchanging the for the superexchange important O atom with p-elements of a different valence electron configuration changes the underlying magnetic exchange mechanism and influence the ground state properties which can be used for tuning properties interesting for technical applications. Four different doping configurations were examined revealing a cell site dependent influence on the magnetic properties. Carbon, for example, changes the AFM coupling present in the Fe1-O-Fe2 configuration into a ferrimagnetic exchange for the Fe1-C-Fe2 bond. Depending on the respective cell site C substitution introduces a ferrimagnetic or AFM ground state. Nitrogen alters the ground state magnetic moment as well and Sulfur introduces large structural distortions affecting the, band gap and the overall AFM coupling inside the doped GaFeO3 simulation cell. We give a detailed discussion on the respective magnetic exchange mechanisms and electronic properties with regard to applications as photocatalysis and use the predictive power of ab initio DFT simulations that may trigger future experiments.