NEWS ABOUT BINUCLEAR OXOFERRATES(II) [1]

By ''reaction with the wall'' of the Fe-cylinders used here we synthesized the new oxoferrates(II) CS6[Fe2O5], CS3.5Rb2.5[Fe2O5] and Rb4K2[Fe2O5] in the form of red single crystals. The structure elucidation via four-circle-diffractometer data shows that the new oxoferrates(II) are isotypic with CS2(Cs0.35K1.65)K2[Fe2O5]. In the structure we have isolated binuclear groups [(O1)2Fe-O(2)-Fe(O1)2]6-. Structure refinements is possible in the centrosymmetrial space group C2/m as well as in the space groups C2 and Cm without centre of symmetry. The existence of two further oxoferrates(II) CS6-xRbx[Fe2O5] and Cs6-xKx[Fe2O5] which can be described as solid solutions was confirmed by power-data.