Magnetic characterization of tetranuclear copper(II) and cobalt(II) exchange-coupled clusters encapsulated in heteropolyoxotungstate complexes. Study of the nature of the ground states

Abstract

This paper presents a magnetic characterization of the heteropolyanions [M 4 (H 2 O) 2 (PW 9 P 34 ) 2 ] 10- and [M 4 (H 2 O) 2 (P 2 W 15 O 56 ) 2 ] 16- (M=Cu(II), Co(II)), with emphasis on the exchange interactions. Their individual heteropolyoxometalate molecules encapsulate a rhomblike arrangement formed by four coplanar MO 6 octahedra sharing edges