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Temperature and pressure-induced spin-state transitions in LaCoO3

György Vankó·Jean-Pascal Rueff·Aleksi Mattila·Zoltán Németh·Abhay Shukla
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Abstract

We report the continuous variation of the spin moment of cobalt in LaCoO3 across its temperature and pressure-induced spin transitions evidenced with Kβemission spectra. The first thermal transition is best described by a transition to an orbitally nondegenerate intermediate spin (S=1) state. In parallel, continuous redistribution of the 3d electrons is also indicated by partial fluorescence yield X-ray absorption spectra. At high pressure, our study confirms that the material becomes low spin between 40 and 70 kbar at room temperature.

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György Vankó, Jean-Pascal Rueff, Aleksi Mattila, Zoltán Németh, Abhay Shukla. 2005-10-21. Temperature and pressure-induced spin-state transitions in LaCoO3. https://doi.org/10.1103/physrevb.73.024424

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