Electrical transport and EPR properties of the alpha, beta, and gamma phases of Fe2WO6

The polymorphic modifications alpha, beta, and gamma Fe2WO6 of the iron (II I) tungstate have been investigated by resistivity and electron paramagneti c resonance (EPR) measurements. The high-electrical resistivity for all pha ses complies with the dominant antiferromagnetic component of the compounds . The EPR spectra comprise a broad exchange narrowed EPR line due to Fe3+ i ons. The broadening of the EPR linewidth is explained in terms of the criti cal spin fluctuations near the antiferromagnetic phase transition. The shif t of the resonance field and the temperature dependence-of the EPR intensit y imply an extended region of short-range order correlations. [S0163-1829(9 9)09535-1].