Synthesis, structural and magnetic studies of an isostructural family of mixed 3d/4f tetranuclear 'star' clusters

DC magnetic studies on new 'star' clusters of formula [Mn(3)Ln(acac)(6)(tea)(2)][Mn(acac)(3)] (Ln = Gd (1) and Dy (2)) and [Fe(3)Ln(acac)(6)(tea)(2)] (Ln = Gd (3) and Dy (4)) show that all cases display weak coupling, with compounds 3 and 4 displaying ferromagnetic J(LnFe) coupling, 3 having a S = 11 ground state.