Hydrothermal synthesis and structures of the homoleptic iodate complexes [M(IO3)6]2- (M = Mo, Zr)

Rb2[Mo(IO3)6] (1), Rb2[Zr(IO3)6] (2), and Cs2[Zr(IO3)6] (3) have been prepared under hydrothermal conditions. These compounds are isostructural and consist of alkali metal cations and isolated [M(IO3)6]2- anions containing transition metals in +4 oxidation state. The [M(IO3)6]2- anions possess 3-bar symmetry with the transition metal centers residing on 3-bar sites. The iodate anions ligate the transition metals through a single oxygen atom. All of the iodate oxygen atoms form long interactions with the alkali metal cations. These interactions result in a contraction of the OMO bond angles along a single three-fold axis. Crystallographic data (193K): 1, trigonal, space group R3-bar, a 11.4048(8)A, c = 11.4062(8)A, Z = 3, Mo Kα, λ = 0.71073, R(F) 2.52% for 43 parameters with 711 reflections with I > 2σ(I); 2, trigonal, space group R3-bar, a = 11.5575(9)A, c = 11.4987(9)A, Z = 3, Mo Kα, λ = 0.71073, R(F) = 2.16% for 43 parameters with 742 reflections with I > 2σ(I); 3, trigonal, space group R3-bar, a 11.768(1)A, c = 11.720(1)A, Z = 3, Mo Kα, λ = 0.71073, R(F) 1.61% for 43 parameters with 781 reflections with I > 2σ(I)