Synthesis, crystal structure refinement, electrical and magnetic properties of BaV13O18 and SrV13O18

Polycrystalline samples of BaV13O18 and SrV13O18 were prepared by solid-state reaction of BaCO3, SrCO3, V2O5 and V at 1773–2073 K in flowing Ar. The crystal structures of BaV13O18 (R-3, ah=12.6293(10) Å, ch=7.0121(4) Å) and SrV13O18 (ah=12.5491(7) Å, ch=6.9878(3) Å) were refined by the Rietveld method using X-ray diffraction data. BaV13O18 exhibited semiconducting behavior with electrical resistivity from 5.8×10−3 to 2.7×10−3 Ω cm at 100–300 K. Electrical resistivity of SrV13O18 ranged from 1.5×10−3 to 1.8×10−3 Ω cm, and it increased slightly up to around 250 K and decreased above 250 K with increasing temperature. Negative Seebeck coefficients of both compounds at 100–300 K indicated that electron was the dominant carrier. BaV13O18 and SrV13O18 showed paramagnetism with the effective magnetic moment of 0.11μB and 0.15μB, respectively, at 10–100 K.