A REFINEMENT OF THE CRYSTAL STRUCTURES OF (NH₄)₂TeBr₆ AND Cs₂TeBr₆

(NH 4 ) 2 TeBr 6 and Cs 2 TeBr 6 crystals have the cubic K 2 PtCl 6 structure with space group: [Formula: see text] with a 0 = 10.728 ± 0.003 Å and 10.918 ± 0.002 Å respectively. The positional coordinate of the bromine atom, and the anisotropic temperature factors of all atoms in the unit cell, have been refined for both crystals by a full matrix least-squares analysis of the three dimensional X-ray diffraction data (R = 0.08). The Te—Br distance, corrected for probable thermal motions of atoms forming the bond, is 2.70 ± 0.01 Å in both crystals.