Large magnetic polyoxometalates containing the Cobalt Cubane '[CoIIICo3II(OH)3(H2O)6-m(PW9O34)]3-' (m = 3 or 5) as a Subunit

Abstract

A synthetic procedure is presented to construct new magnetic polyoxometalates (POMs) containing one or two subunits of '[CoIIICo3II(OH)3(H2O)6-m(PW9O34]3-' (m = 3 or 5). The substitution of the water ligands present in these subunits by oxo or hydroxo ligands belonging to other POM fragments, gives rise to four, larger POM anions: [Co7(OH)6(H2O)6(PW9O34)2]9- (2), [Co7(OH)6(H2O)4(PW9O34)2]n9n- (2'), [Co11(OH)5(H2O)5(W6O24)(PW9O34)3]22- (3) and [(Co4(OH)3(H2O)(PW9O34))2(K⊂(H2W12O41)2)(Co(H2O)4)2]17- (4). The crystal structures, magnetic characterization and stabilities in aqueous solutions of these POM derivatives are also presented.