A series of di-, tri- and tetranuclear lanthanide clusters with slow magnetic relaxation for Dy(2) and Dy(4)

Abstract

A series of dinuclear, trinuclear and tetranuclear lanthanide complexes, formulated as [Nd(2)(Acc)(6)(H(2)O)(4)](3) [Nd(2)(Acc)(6)(H(2)O)(6)]center dot Cl(24)center dot 8H(2)O (1), [Dy(2)(Acc)(4)(H(2)O)(8)]center dot Cl(6)center dot 5.89H(2)O (2), [Ln(3)(Acc)(10)(H(2)O)(6)]center dot(ClO(4))(9)center dot 4H(2)O (Ln La, (3); Nd, (4)) and [Ln(4)(mu(3)-OH)(4)(Acc)(6)(H(2)O)(7)(ClO(4))]center dot(ClO(4))(7)center dot 11H(2)O (Ln Dy, (5); Yb, (6)), have been synthesized through the reaction of 1-amino cyclohexanel-carboxylic acid (Acc) and LnCl(3)/Ln(ClO(4))(3). Crystal structure analysis reveals that complexes 1 and 2 show dinuclear lanthanide cluster, complexes 3 and 4 have three lanthanide ions with a linear arrangement, while complexes 5 and 6 exhibit a cubane-like [Ln(4)(mu 3-OH)(4)](8+) (Ln Dy and Yb) cluster core. Their structural variations are attributed to the effect of anions and lanthanide contraction. Magnetic studies indicate that the Dy(2) and Dy(4) clusters exhibit slow relaxation of magnetization.