Magnetic structures of the ordered trirutiles Cr2WO6, Cr2TeO6 and Fe2TeO6

Cr2WO6, Cr2TeO6 and Fe2TeO6 belong to chemical space group P42/mnm (Z = 2) and are antiferromagnetically ordered at 4.2°K. Neutron diffraction results for the ordered state show that the magnetic ions have collinear spin arrangements in a magnetic cell identical with the chemical cell, with 3 d-ion moments of 2.14 μB, 2.45 μB and 4.19 μB, respectively, for the three compounds. Although Cr2TeO6 and Cr2WO6 have nearly identical Cr-O-Cr bond angles and bond distances, the former is magnetically body-centered while the latter is anti-body-centered. In both cases the Cr spins lie in the basal plane. Fe2TeO6 is structurally equivalent to Cr2TeO6 except that the spin is directed along the c-axis. V2WO6 has been synthesized and found to have the trirutile structure. Preliminary neutron diffraction results indicate that it is magnetically ordered at 4.2°K with the Cr2WO6 structure.