Syntheses, structures and magnetic properties of two copper(II) diphosphonates: [NH3(CH2)(2)NH3](2)[Cu-2(hedp)(2)]center dot H2O and [NH3CH(CH3)CH2NH3](2)[Cu-2(hedp)(2)] (hedp=1-hydroxyethylidenediphosphonate)

This paper describes the syntheses and characterization of two new copper(I I) diphosphonates: [NH3(CH2)(2)NH3](2) [Cu-2(hedp)(2)].H2O (1) and [NH3CH(C H3)CH2NH3](2) [Cu-2 (hedp)(2)] (2) (hedp = 1-hydroxyethylidenediphosphonate ). Both compounds exhibit similar one-dimensional linear chain structures. The symmetrical {Cu-2(hedp)(2)} dimers are connected by edge-shared {CuO5} square pyramids and form infinite chains. The Cu(II) ions are alternately b ridged by O-P-O groups and O atoms. The Cu-O-Cu angles are 95.8(1) and 96.1 (1)degrees for 1 and 2, respectively. Their magnetic properties show modera tely strong antiferromagnetic interactions in both compounds.