| Polycrystalline samples of Zn3Fe4V6O24 prepared by a solid-state reaction technique have been studied by DC magnetic and Electron Paramagnetic Resonance (EPR) methods in the 2-300K temperature range. Static magnetic susceptibility measurements have shown the presence of a strong antiferromagnetic interaction (Curie-Weiss temperature θ=-101K) in the Fe3+ sublattice. The effective magnetic moment of a unit cell (about 11 mB for four iron ions) indicates significant presence of antiferromagnetic correlations. At low temperatures (3K and 6K) clear indications of two spin-glass states have been recorded in the temperature dependence of susceptibility. The recorded EPR spectra consist of two components: a very broad line registered in a high temperature range (above 15K) and a narrow line below 15K. The EPR amplitude of the broad component decreases with a temperature decrease while the opposite trend has been observed for the narrow line. On decreasing the temperature from RT the broad line shifts slightly towards a higher magnetic field and its linewidth increases. Large changes of the g-factor and linewidth of this line are observed below 75K. The temperature dependence of the EPR integral intensity of the broad line shows a marked anomaly at about 220K in contrast to the static magnetic susceptibility where no such irregularity has been observed. The studied magnetic properties of Zn3Fe4V6O24 are discussed in terms of an inherent magnetic inhomogeneity of this compound with competing magnetic interactions and spin clusters. |
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