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arXiv · 1111.4855

Structural and insulator-to-metal phase transition at 50 GPa in GdMnO3

J. Agostinho Moreira·A. Almeida·J. Oliveira·V. H. Rodrigues·M. M. R. Costa·P. B. Tavares·P. Bouvier·M. Guennou·J. Kreisel
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Abstract

We present a study of the effect of very high pressure on the orthorhombic perovskite GdMnO3 by Raman spectroscopy and synchrotron x-ray diffraction up to 53.2 GPa. The experimental results yield a structural and insulator-to-metal phase transition close to 50 GPa, from an orthorhombic to a metrically cubic structure. The phase transition is of first order with a pressure hysteresis of about 6 GPa. The observed behavior under very high pressure might well be a general feature in rare-earth manganites.

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J. Agostinho Moreira, A. Almeida, J. Oliveira, V. H. Rodrigues, M. M. R. Costa, P. B. Tavares, P. Bouvier, M. Guennou, J. Kreisel. 2011-11-21. Structural and insulator-to-metal phase transition at 50 GPa in GdMnO3. https://arxiv.org/abs/1111.4855

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