CRYSTAL-STRUCTURE OF CESIUM SODIUM HEXATHIOCYANATOBISMUTHATE CS2NA[BI(SCN)(6)] AND CHARACTERIZATION OF CS2NA[BI(SCN)(6-X)CL-X] AND CS2NA[BI-2(SCN)(9-X)CL-X] COMPLEXES BY X-RAY-POWDER DIFFRACTION

Cs2Na[Bi(SCN)(6)] crystallizes in the trigonal space group P $($) over bar$$ 3 with one formal molecule per unit cell. M = 846.25, a = 7.189 (1), c = 10.580(2) Angstrom, V = 473.5(1) Angstrom(3), D-x = 2.967 g c m(-3), mu(MoK alpha) = 13.70 mm(-1), F(000) = 378. Final R = 0.029 for 917 absorption-corrected reflections. The structure consists of infin ite [Bi(SCN)(6)Na](2-)(infinity) anionic chains along the c axis with slightly distorted octahedral Bi-6S and Na-6N coordination and Cs+ ion s surrounded by three anionic chains with irregular coordination by si x N and three S atoms. X-ray powder diffractograms of three complexes, Cs2Na[Bi(SCN)(6-x)Cl-x] with x = 2, 3 and 4, indicate that the mixed complexes are not isostructural and can be indexed in different orthor ombic unit cells with a = 14.617(8), b = 12.32(1), c = 10.769(6) Angst rom for x = 2; a = 15.37(1), b = 10.81(1), c = 10.287(6) Angstrom for x = 3 and a = 14.662(7), b = 14.366(7), c = 7.932(4) Angstrom for x = 4. The two dinuclear complexes Cs2Na[Bi-2(SCN)(9-x)Cl-x] with x = 2 an d 3, despite the large similarity of their diffractograms, are not iso structural and can be indexed in different orthorombic unit cells with a = 14.79(1), b = 13.72(1), c = 10.591(5) Angstrom for x = 2 and a = 18.423(8), b = 15.657(7), c = 7.410(7) Angstrom for x = 3.