The oxides 1-4 are prepared in a single step I y the reaction of a precursor containing a transition or posl-transition element, the bidentate amine, and V,Oj in water at I70 C, and are isolated as highly crystalline, thin black plates. Since no external reducing agent is employed, the amine presumably serves i n this capacity. These materials, (L,M),. [VO,], where L = bidentate amine, M = Cu or Zn, 0.16

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A 3-D, open framework, mixed valence iron phosphate, [H3NCH2CH2NH3]2[Fe4O(PO4)4]·H2O, which contains organic ethylenediammonium dications in the framework voids, has been prepared via hydrothermal synthesis and has been characterized by single-crystal X-ray diffraction, magnetic susceptibility, and variable temperature Mössbauer spectroscopy. Crystal data:  tetragonal, space group I4̄2m with a = 10.1383(8) Å, c = 9.628(1) Å, V = 989.6(1) Å3, Z = 2, and R(R w) = 7.7(6.5) for 276 reflections (I > 3σ(I)) and 32 variables. The fundamental building block of the structure is a novel cubane-like cluster with trigonal bipyramidal iron and tetrahedral phosphorus atoms lying at alternate vertexes of a cube with a tetrahedrally coordinated oxygen atom at the center of the cube. Each cluster is linked by eight Fe−O−P bonds that extend along what would be all 〈111〉 directions of the putative cube to eight similar clusters to form a framework that is only slightly distorted (by the presence of the organic cations) from cubic 4̄3m symmetry. Mössbauer and ac magnetic susceptibility measurements show that equal amounts of valence trapped Fe2+ and Fe3+ are present, which undergo long range magnetic ordering at ∼12 K.

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