| Two new compounds from the multicomponent vanadates Me2InV3O11-δ (Me=Mg, Zn) have been synthesized and investigated by electron paramagnetic resonance (EPR) at room temperature. XRD measurements have shown that they are isostructural with the magnetic system Me2FeV3O11-δ. The EPR spectra of the Mg2InV3O11-δ and Zn2InV3O11-δ compounds originated from defect centers consisting of V(IV) ions and clusters. For Mg2InV3O11-δ the EPR spectrum with hyperfine structure was observed with the following spin Hamiltonian parameters: g|| = 1.93, g⊥ =1.94 and A|| = 180.10-4 cm-1, A⊥ = 50.10-4 cm-1. A weak line attributed to the forbidden ΔMS =±2 transition was registered at low magnetic field of 163 mT. For the Zn2InV3O11-δ compound two resonance lines were observed; one centered at g=1.967(3) with linewidth ΔH=4.8(9) mT and another at g=2.82(1) with ΔH=28(1) mT. The appearance of the EPR spectra was correlated with oxygen deficiency phenomena playing an active role in determining the magnetic properties of these compounds. |
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