SYNTHESIS AND CRYSTAL-STRUCTURE OF THE NEW ISOTYPIC COMPOUNDS KBI6O9X(X = CL, BR, I)

The new quaternary compounds KBi6O9X (X = Cl, Br, I) were synthesized with yields of about 90% by reaction of BiX3 with >10 N KOH (X = Br, I ) and by reaction of a H[BiCl4] solution with solid KOH. Single crysta ls of the three compounds were grown by addition of diluted H[BiX4] so lutions to >10 N KOH. The crystal structures were solved and refined t o R-1 = 0.0214, 0.0199, and 0.0205, respectively. The three compounds are isotypic; they crystallize with space group Ia(3) over bar d and Z = 16. K, Bi, X positions correspond to a distorted bce lattice. The ( K, X) substructure consists of arrays of nonintersecting linear ''chai ns'' parallel to [111].