SYNTHESES AND CRYSTAL-STRUCTURES OF THE POLYSELENIDO COMPLEXES (PPH4)6[M(SE4)2]2[WSE4] BULLET DMF WITH M = ZINC AND MERCURY

The title compounds have been prepared by the reactions of the acetates of zinc and mercury, respectively, with excess (PPh4)2WSe4 in boiling dimethylformamide, forming black-red single crystals. According to the X-ray structure determinations both compounds crystallize isotypically in the space group I2/a with four formula units per unit cell. (PPh4)6[Zn(Se4)2]2[WSe4] . DMF: a = 2 888.1(6), b = 1 740.3(2), c = 2 893.9(4) pm, beta = 90.47(1)-degrees. 3 230 observed unique reflections, R = 0.099. (PPh4)6[Hg(Se4)2]2[WSe4] . DMF: a = 2 891.8(5), b = 1 738.0(4), c = 2 920.1(5) pm, beta = 90.29(2)-degrees. 2 978 observed unique reflections, R = 0.115%. The compounds consist of PPh4+ ions, spirocyclic octaseleno metallates [M(Se4)2]2-, tetrahedral WSe42- ions, and disordered DMF molecules.