Crystal structure and magnetism in CoSb2O6 and CoTa2O6

CoSb2O6 was investigated by neutron diffraction and magnetic susceptibility techniques. The structure found was tetragonal, of the trirutile type, with space group P42mnm, a = 4.6495(2)Å, c = 9.2763(6)Å. Low-temperature neutron data gave no evidence of structural change down to 20 K. Susceptibility data showed a deviation from Curie-Weiss behavior below 100 K and a maximum at 35 K associated with low-dimensional ordering. A Curie-Weiss law fit …