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arXiv · 1408.3997

Magnetoelectric properties of $A_2$[FeCl$_5$(H$_2$O)] with $A = $ K, Rb, Cs

M. Ackermann·T. Lorenz·P. Becker·L. Bohaty
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Abstract

The compounds $A_2$[FeCl$_5$(H$_2$O)] with $A=$ K, Rb, Cs are identified as new linear magnetoelectric materials. We present a detailed investigation of their linear magnetoelectric properties by measurements of pyroelectric currents, dielectric constants and magnetization. The anisotropy of the linear magnetoelectric effect of the K-based and Rb-based compound is consistent with the magnetic point group $m'm'm'$, already reported in literature. A symmetry analysis of the magnetoelectric effect of the Cs-based compound allows to determine the magnetic point group $mmm'$ and to develop a model for its magnetic structure. In addition, magnetic-field versus temperature phase diagrams are derived and compared to the closely related multiferroic (NH$_4$)$_2$[FeCl$_5$(H$_2$O)].

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M. Ackermann, T. Lorenz, P. Becker, L. Bohaty. 2014-08-18. Magnetoelectric properties of $A_2$[FeCl$_5$(H$_2$O)] with $A = $ K, Rb, Cs. https://doi.org/10.1088/0953-8984/26/50/506002

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