Sodium Cobalt Aminomethylidenediphosphonate with a Novel Open Framework Structure

This paper reports the synthesis and crystal structure of a cobalt aminomethylenediphosphonate compound NaCo2{NH3CH(PO3) (PO3H0.5)}2(H2O)2·xH2O (1). It shows a novel open framework structure in which layers of Co2{NH3CH(PO3)(PO3H0.5)}2(H2O)2 are connected by NaO6 linkages. The magnetic studies show a dominant antiferromagnetic exchange between the Co(II) ions