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arXiv · 1912.05997

Cluster glass behavior of frustrated birnessites AxMnO2*yH2O (A = Na, K)

L. D. Kulish·R. Scholtens·G. R. Blake
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Abstract

We report on the synthesis and magnetic properties of frustrated Na0.22MnO2*0.39H2O and K0.6MnO2*0.48H2O with the birnessite structure. The structure, static and dynamic magnetic properties of the compounds are investigated in detail. A combination of DC and AC magnetic susceptibility measurements and magnetization decay measurements reveal cluster glass behavior below the freezing temperature of 4 K for Na-birnessite and 6 K for K-birnessite. The frequency dependence of the freezing temperature is analyzed on the basis of dynamic scaling laws including the critical slowing down formula and the Vogel-Fulcher law, which further confirm cluster glass formation in both compounds.

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L. D. Kulish, R. Scholtens, G. R. Blake. 2019-12-12. Cluster glass behavior of frustrated birnessites AxMnO2*yH2O (A = Na, K). https://doi.org/10.1103/physrevb.100.214435

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