CRYSTAL-STRUCTURE OF THE ADDUCT -ACID-DISODIUM-ETHYLENEDIAMINETETRAACETATE-WATER(1 1/2)/

The title compound crystallizes in the form of racemic twins of hexago nal symmetry from slightly acidic aqueous solutions containing H6TeO6 and Na(2)H(2)edta in a broad range of molar ratios. The crystals are o f excellent quality and high diffraction power, thus enabling the stru cture determination with a precission not routinely attainable by conv entional single crystal X-ray diffraction (R = 0.015 at room temperatu re). The building units of the structure, held together by a system of hydrogen bonds, are the octahedral Te(OH)(6) molecule, the H(2)edta(2 -) anion with protonated nitrogens, two water molecules and two sodium cations surrounded by ten oxygens in the O4Na(mu-O)(2)NaO4 moiety of irregular geometry.