Abstract
The results of an electron paramagnetic resonance study of a new product, namely ethylenediammonium copper(II) diphosphate monohydrate of chemical formula Cu(NH3(CH2)(2)NH3)P2O7 . H2O, are presented. The x-ray diffraction has shown the existence of two types of copper(II) coordination polyhedron for each elementary mesh in this compound. Each polyhedron consists of a copper ion surrounded by five oxygenated ligands stoning from two P2O7 groups and a water molecule. Fair agreement between these results and those obtained by x-ray diffraction is observed. In particular the organization of oxygen atoms as pyramids with a square plane around the copper(II) ions is confirmed. The existence of two magnetically non-equivalent sites of copper per mesh is evidenced.