Structural, magnetic and dielectric properties of a new double perovskite Pr2CoTiO6

A new double perovskite Pr2CoTiO6 has been synthesized by conventional solid state method. The structure of the compound has been investigated through powder x-ray and neutron diffraction techniques. The Rietveld refinement of the structural data shows that the compound crystallizes in the monoclinic structure (S.G. P2(1)/n # 14)). The refined cell parameters are: a = 5.4800(6) (A) over circle, b = 5.6221(6) (A) over circle, c = 7.7700(9) (A) over circle, beta = 89.98(4)degrees. Monoclinic distortion phi associated with the distortion of the CoO6- and TiO6- octahedra is 13.7 degrees. Magnetic measurements down to 4 K show antiferromagnetic-like ordering of the material, T-N similar to 17 K with paramagnetic effective magnetic moment mu(eff) = 6.92 mu(B). At room temperature, the dielectric constant and dielectric loss of Pr2CoTiO6 are 45.5 and 1.2 respectively.