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arXiv · 1602.00102

A new high pressure form of Ba3NiSb2O9

Céline Darie·Christophe Lepoittevin·Holger Klein·Stéphanie Kodjikian·Pierre Bordet·Claire V. Colin·Oleg I. Lebedev·Catherine Deudon·Christophe Payen
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Abstract

The interest in finding experimental realization of Quantum Liquid Spin phases leads us to elaborate polycrystalline samples of the 6H-B phase of Ba3NiSb2O9 . This structure shows Ni triangular planes and the first magnetic characterizations confirm the absence of any magnetic order as expected for QLS. The samples were synthesized by treatment under HP-HT of the 6H-A phase of Ba3NiSb2O9. The optimized synthesis conditions were 2.5 GPa and 620{\deg}C. By combining several technics as XRD, NPD and TEM we show that even the obtained compound is in fact a new form of Ba3NiSb2O9, that corresponds to a new stacking along c. This preserves the presence of Ni planes but results in a loss of the hexagonal symmetry. The TEM is helpful to conclude to a trigonal symmetry at a scale of 10nm.

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Céline Darie, Christophe Lepoittevin, Holger Klein, Stéphanie Kodjikian, Pierre Bordet, Claire V. Colin, Oleg I. Lebedev, Catherine Deudon, Christophe Payen. 2016-01-30. A new high pressure form of Ba3NiSb2O9. https://doi.org/10.1016/j.jssc.2016.02.011

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