Octahedral hexahydroxo rhenium cluster complexes [Re₆Q ₈(OH)₆]^4-.(Q = S, Se): Synthesis, structure, and properties

Two novel rhenium cluster compounds, K₄[Re₆S ₈(OH)₆]·8H₂O (1) and K ₄[Re₆Se₈(OH)₆]·8H ₂O (2), containing octahedral cluster chalcogenide anionic complexes [Re₆Q₈(OH)₆]^4- with terminal hydroxo ligands have been synthesized by the reaction of Re₆Q ₈Br₂ (Q = S, Se) with molten KOH. Two chalcohalide compounds, one known (Cs₄[Re₆S₈Br ₆]·2H₂O, 3) and another new (Cs₃[Re ₆Se₈Cl₆]·2H₂O, 4), were prepared by reactions of 1 and 2 with CsX and HX (X = Br, Cl) in an aqueous solution. Compounds 1, 2, and 4 have been characterized by the single-crystal X-ray diffraction method. Compounds 1 and 2 are crystallized in triclinic space group P1 with one formula unit in the cell of dimensions a = 8.4936(8) Å, b = 8.9101(11) Å, c = 10.5940(13) Å, α = 77.935(11)°, β = 75.933(9)°, γ = 71.244(10)°, V = 728.9(1) ų (compound 1) and a = 8.613(1) Å, b = 8.996(1) Å, c = 10.057(1) Å, α = 78.587(2)°, β = 77.811(2)°, γ = 71.728(2)°, V = 715.9(2) ų (compound 2). Compound 4 crystallizes in the monoclinic space group P2₁/n with two formula units in the cell of dimensions a = 9.819(3) Å, b = 12.925(4) Å, c = 11.756(4) Å, β = 113.38(3)°, V = 1369.6(8) ų. Compounds 1 and 2 display luminescent properties.