Bis{tris-[3-(2-pyrid-yl)-1H-pyrazole]nickel(II)} dodeca-molybdosilicate tetra-hydrate

Bis{tris[3-(2-pyridyl)pyrazole]manganese(II)} dodecamolybdosilicate hexahydrate

The title compound, [Mn(C₈H₇N₃)₃]₂[SiMo₁₂O₄₀]·6H₂O, consists of an [SiMo₁₂O₄₀]⁴⁻ heteropolyanion, lying on a centre of inversion, and a complex [Mn(C₈H₇N₃)₃]⁴⁺ cation. The Mn^II atom of the cation is hexa­coordinated in a distorted octa­hedral geometry by six N atoms from three chelating 3-(2-pyrid­yl)pyrazole ligands. In the heteropolyanion, the four O atoms of the tetra­hedral SiO₄ group each half-occupy eight sites due to Si lying on the centre of inversion. N—H⋯O and O—H⋯O hydrogen bonding mediated by the water mol­ecules leads to a consolidation of the structure.

Bis{tris-[3-(2-pyrid-yl)-1H-pyrazole]iron(II)} tetra-deca-molybdo(V,VI)silicate

The asymmetric unit of the title compound, [Fe(C₈H₇N₃)₃]₂[SiMo₁₄O₄₄], consists of a complex [Fe(C₈H₇N₃)₃]²⁺ cation and half of a derivative of an α-Keggin-type anion, [SiMo₁₄O₄₄]⁴⁻. In the mixed-valent Mo^V/VI anion, the α-Keggin type core is capped on two oppositely disposed tetra­gonal faces by additional (MoO₂) units. The [SiMo₁₄O₄₄]⁴⁻ anion shows disorder. Two O atoms of the central SiO₄ group ( symmetry) are equally disordered about an inversion centre. Moreover, two of the outer bridging O atoms and the O atoms of the capping (MoO₂) unit are likewise disordered. The Fe²⁺ cation is surrounded in a slightly distorted octa­hedral coordination by six N atoms from three 3-(2-pyrid­yl)-1H-pyrazole ligands. N—H⋯O hydrogen bonding between the cations and anions leads to a consolidation of the structure.

Tris{aqua-bis[3-(2-pyrid-yl)-1H-pyrazole]copper(II)} di-μ(9)-arsenato-hexa-triaconta-μ(2)-oxido-octa-deca-oxidoocta-deca-molybdate(VI)

The title compound, [Cu(C(8)H(7)N(3))(2)(H(2)O)](3)[As(2)Mo(18)O(62)], consists of two subunits, viz. an α-Dawson-type [As(2)Mo(18)O(62)](6-) anion and a complex [Cu(C(8)H(7)N(3))(2)(H(2)O)](2+) cation. The copper(II) ion (site symmetry .2) is penta-coordinated in a distorted square-pyramidal manner by four N atoms from two chelating 3-(2-pyrid-yl)pyrazole ligands in equatorial positions and one water mol-ecule in the apical position. In the heteropolyanion, two O atoms of the AsO(4) group (3. symmetry) are equally disordered about the threefold rotation axis. N-H⋯O and O-H⋯O hydrogen bonding between the neutral mol-ecules and the water mol-ecules leads to a consolidation of the structure.