The frequency and temperature dependences of the magnetic susceptibility and the ac electrical conductivity in magnetoelectric were investigated. The zero-field-cooled-field-heated magnetic susceptibility reveals phase transitions at 14.2 and 36.6 K. The phase below 36.6 K is ferromagnetic. At temperatures below 200 K, the ac conductivity and dielectric constant follow the universal dielectric response (UDR), being typical for hopping or tunneling of localized charge carriers. A detailed analysis of the temperature dependence of the UDR parameter in terms of the theoretical model for tunneling of small polarons revealed that below 200 K, this mechanism governs the charge transport in the magnetoelectric fluoride system.
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