Au₃SnCuP₁₀ and Au₃SnP₇: Preparation and crystal structures of Au₃Sn heterocluster polyphosphides

The formation of Au₃Sn heteroclusters completes the homologous series of M₃Sn clusters observed for transition metal main-group polyphosphides. Au₃SnCuP₁₀ is cubic, space group F43m (No. 216) with lattice parameter a = 10.3953(5) Å. The structure refinement yielded R1 = 0.0353 and wR2 = 0.0726 for 154 F² values and 13 variables. Disordered Au₃Sn heteroclusters occupy all octahedral, and adamantane like P₁₀ cages one half of the tetrahedral voids of a face-centred cubic (fcc) arrangement of copper. Ordered and orientationally disordered Au₃Sn heteroclusters have been observed for Au ₃SnP₇, embedded in a _∞¹[P ₇] polyphosphide unit formed by six-membered phosphorus rings in chair conformation which are linked by a P-bridge. Au₃SnP₇ is monoclinic, space group P2₁/m (No. 11) with lattice parameters of a = 6.219(2), b = 10.836(2), c = 6.318(2) Å, β = 108.65(2)°, V = 403.4(2) ų, R1 = 0.0412 and wR2 = 0.0745, 1261 F² values and 56 variables. Au₃SnP₇ with disordered Au ₃Sn clusters has slightly larger lattice parameters of a = 6.343(3), b = 10.955(3), c = 6.372(3) Å, β = 108.63(2)°, V = 419.6(2) ų, R1 = 0.0324 and wR2 = 0.0691, 1131 F² values and 58 variables.