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arXiv · 0711.0280

Magnetism without magnetic impurities in oxides ZrO2 and TiO2

Frantisek Maca·Josef Kudrnovsky·Vaclav Drchal·Georges Bouzerar
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Abstract

We perform a theoretical study of the magnetism induced in transition metal dioxides ZrO2 and TiO2 by substitution of the cation by a vacancy or an impurity from the groups 1A or 2A of the periodic table, where the impurity is either K or Ca. In the present study both supercell and embedded cluster methods are used. It is demonstrated that the vacancy and the K-impurity leads to a robust induced magnetic moment on the surrounding O-atoms for both the cubic ZrO2 and rutile TiO2 host crystals. On the other hand it is shown that Ca-impurity leads to a non magnetic state. The native O-vacancy does not induce a magnetic moment in the host dioxide crystal.

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Frantisek Maca, Josef Kudrnovsky, Vaclav Drchal, Georges Bouzerar. 2007-11-02. Magnetism without magnetic impurities in oxides ZrO2 and TiO2. https://doi.org/10.1063/1.2936858

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