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arXiv · 0803.1312

Crystal-to-stripe reordering of sodium ions in NaxCoO2 (x>=0.75)

D. J. P. Morris·M. Roger·M. J. Gutmann·J. P. Goff·D. A. Tennant·D. Prabhakaran·A. T. Boothroyd·E. Dudzik·R. Feyerherm·J. -U. Hoffmann·K. Kiefer
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Abstract

The sodium reordering in NaxCoO2 in the vicinity of room temperature is rationalized at high x in terms of phase transitions between square and striped phases. A striking hexagon-of-hexagons diffraction pattern observed for x=0.78 can be reproduced using coexisting square and striped phases that are related by simple shear deformations. All compositions exhibit a partial melting transition to a disordered stripe phase just below room temperature, which alters the topology of the electrical conduction pathways.

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D. J. P. Morris, M. Roger, M. J. Gutmann, J. P. Goff, D. A. Tennant, D. Prabhakaran, A. T. Boothroyd, E. Dudzik, R. Feyerherm, J. -U. Hoffmann, K. Kiefer. 2009-07-31. Crystal-to-stripe reordering of sodium ions in NaxCoO2 (x>=0.75). https://doi.org/10.1103/physrevb.79.100103

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