RESUMO
The title compound, (C(4)H(12)N)(4)[Ta(6)Cl(18)]Cl, crystallizes in the cubic space group Fm-3m. The crystal structure contains two different types of coordination polyhedra, i.e. four tetrahedral [(CH(3))(4)N](+) cations and one octahedral [(Ta(6)Cl(12))Cl(6)](3-) cluster anion, and one Cl(-) ion. The presence of three different kinds of Cl atoms [bridging (mu(2)), terminal and counter-anion] in one molecule makes this substance unique in the chemistry of hexanuclear halide clusters of niobium and tantalum. The Ta(6) octahedron has an ideal O(h) symmetry, with a Ta-Ta interatomic distance of 2.9215 (7) A.
RESUMO
The title compound, [Ta(6)Br(12)(H(2)O)(6)](Br(0.4)Cl(1.6)) x 8H(2)O, crystallizes in space group P 1 macro. The structure contains two crystallographically independent [Ta(6)Br(12)(H(2)O)(6)](2+) cluster cations forming distinct layers parallel to the ab plane. The compound is isoconfigurational with the double salts [Ta(6)Br(12)(H(2)O)(6)]X(2) x trans-[Ta(6)Br(12)(OH)(4)(H(2)O)(2)] x 18H(2)O (X = Cl, Br).
RESUMO
The novel title compound, [(CH(3))(4)N](2)[Ta(6)Br(12)(H(2)O)(6)]Br(4) x 2H(2)O, with a [Ta(6)Br(12)]2+ cluster unit, has been prepared and structurally characterized. The compound crystallizes in space group C2/c, with a twofold axis passing through the cluster and the centre of symmetry located between the clusters. The nearest neighbouring cluster units are aligned along the crystallographic c axis, forming a one-dimensional chain pattern.