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arXiv · 0806.0493

Melting of the Na layers in solid Na0.8CoO2

M. Weller·A. Sacchetti·H. R. Ott·K. Mattenberger·B. Batlogg
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Abstract

Data of 23Na NMR spectra- and relaxation measurements are interpreted as suggesting that, upon increasing temperature the Na layers in Na0.8CoO2 adopt a 2D liquid state at T=291 K. The corresponding first order phase transition is preceded by a rapidly increasing mobility and diffusion of Na ions above 200K. Above 291 K the 23Na NMR response is similar to that previously observed in superionic conductors with planar Na layers.

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M. Weller, A. Sacchetti, H. R. Ott, K. Mattenberger, B. Batlogg. 2009-01-09. Melting of the Na layers in solid Na0.8CoO2. https://doi.org/10.1103/physrevlett.102.056401

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