X-ray powder diffraction studies of Tl2TeBr6 and Tl2TeI6

The crystal structures of Tl2TeBr6 and Tl2TeI6 have been determined using X-ray powder diffraction techniques. Tl2TeBr6 crystallizes in the tetragonal space group P4/mnc, with the lattice parameters: a=7.468(1) Å, c=10.682(2) Å, Z=2. Tl2TeI6 crystallizes in the monoclinic space group P21/c, with the lattice parameters: a=7.765(2) Å, b=8.174(2) Å, c=13.756(5) Å, β=124.2(1)°, Z=2. The Rietveld refinement procedures were stopped when the intensity residuals RB=0.038 for Tl2TeBr6 and RB=0.049 for Tl2TeI6 had been reached. The crystal structures of both investigated ternary halides belong to the large family of K2PtCl6-related structures.