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Magnetic susceptibility study of hydrated and non-hydrated NaxCoO2-yH2O single crystals

F. C. Chou·J. H. Cho·Y. S. Lee
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Abstract

We have measured the magnetic susceptibility of single crystal samples of non-hydrated NaxCoO2 (x ~ 0.75, 0.67, 0.5, and 0.3) and hydrated Na0.3CoO2-yH2O (y ~ 0, 0.6, 1.3). Our measurements reveal considerable anisotropy between the susceptibilities with H||c and H||ab. The derived anisotropic g-factor ratio (g_ab/g_c) decreases significantly as the composition is changed from the Curie-Weiss metal with x = 0.75 to the paramagnetic metal with x = 0.3. Fully hydrated Na0.3CoO2-1.3H2O samples have a larger susceptibility than non-hydrated Na0.3CoO2 samples, as well as a higher degree of anisotropy. In addition, the fully hydrated compound contains a small additional fraction of anisotropic localized spins.

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F. C. Chou, J. H. Cho, Y. S. Lee. 2004-06-01. Magnetic susceptibility study of hydrated and non-hydrated NaxCoO2-yH2O single crystals. https://doi.org/10.1103/physrevb.70.144526

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