Octahedral Molybdenum Cluster Cyanide Complexes with Selenide and Halide Ligands in the Cluster Core

Two new octahedral molybdenum cluster cyanide complexes with mixed selenide/halide ligands in the cluster core, Cs 5 [Mo 6 Se 3.6 Cl 4.4 (CN) 6 ] ( 1 ) and Cs 5 [Mo 6 Se 3.4 Br 4.6 (CN) 6 ] ( 2 ), have been synthesized by the reaction of Mo 6 Cl 12 or Mo 6 Br 12 with an aqueous solution of Cs 2 Se 3 , and then with an aqueous solution of KCN. Both compounds have been characterized by single‐crystal X‐ray diffraction methods. The compounds are isostructural and crystallize in the trigonal space group P $\bar 3$ c 1with two formula units per unit cell. The unit cell dimensions at 153 K are a = 9.8895(9) Å, c = 19.395(3) Å, V = 1642.7(3) Å 3 ( 1 ) and a = 9.9805(9) Å, c = 19.763(2) Å, V = 1704.9(3) Å 3 ( 2 ). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)