Synthesis, crystal structure, thermal and magnetic properties of [Mn(H2O)(6)][Cu(pdta)]center dot 2H(2)O (pdta=1,3-propylenediamine-N,N,N ' N '-tetraacetate)

On mixing concentrated aqueous solutions of pdta, Cu(II) and Mn(II) in the ratio 1:1:1 at pH 4.5, single crystals of the complex [Mn(H2O)(6)] [Cu(pdta )] . 2H(2)O (1) (pdta = 1,3-propylenediamine-N,N,N'N'-tetraacetate) were ob tained. X-ray structural analysis revealed that in the anion [Cu(pdta)](2-) the coordination polyhedron around the Cu(II) ion can be described as a te tragonaly distorted CuN2O4 octahedron, whereas the cation [Mn(H2O)(6)](2+) can be described as a very regular MnO6 octahedron. Thermogravimetric analy sis shows that at 110 degrees C compound 1 loses its eight water molecules yielding the anhydrous compound [MnCu(pdta)] (2). Variable-temperature magn etic susceptibility measurements indicate that no magnetic interactions are present in 1 while weak antiferromagnetic interactions occur in 2. (C) 200 0 Elsevier Science Ltd All rights reserved.