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arXiv · 1904.13189

Antiferromagnetism in kagome $α$-Cu$_{3}$Mg(OH)$_6$Br$_2$

Yuan Wei·Zili Feng·Clarina dela Cruz·Wei Yi·Zi Yang Meng·Jia-Wei Mei·Youguo Shi·Shiliang Li
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Abstract

The antiferromagnetism in $α$-Cu$_3$Mg(OH)$_6$Br$_2$ was studied by magnetic-susceptibility, specific-heat and neutron-diffraction measurements. The crystal structure consists of Cu$^{2+}$ kagome layers with Mg$^{2+}$ ions occupying the centers of the hexagons, separated by Br$^{1-}$ ions. The magnetic system orders antiferromagnetically at 5.4 K with the magnetic moments aligned ferromagnetically within the kagome planes. The ordered moment is 0.94 $μ_B$, suggesting little quantum and geometrical fluctuations. By comparing the magnetic and specific-heat properties with those of the haydeeite, we suggest that $α$-Cu$_3$Mg(OH)$_6$Br$_2$ may be described by the two-dimensional spin-$1/2$ Heisenberg kagome model and is in the region of the ferromagnetic-order side of the phase diagram.

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Yuan Wei, Zili Feng, Clarina dela Cruz, Wei Yi, Zi Yang Meng, Jia-Wei Mei, Youguo Shi, Shiliang Li. 2019-04-30. Antiferromagnetism in kagome $α$-Cu$_{3}$Mg(OH)$_6$Br$_2$. https://doi.org/10.1103/physrevb.100.155129

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