A series of di-, tri- and tetranuclear lanthanide clusters with slow magnetic relaxation for Dy2 and Dy4

Abstract

A series of dinuclear, trinuclear and tetranuclear lanthanide complexes, formulated as [Nd₂(Acc)₆(H₂O)₄]₃ [Nd₂(Acc)₆(H₂O)₆]·Cl₂₄·8H₂O (1), [Dy₂(Acc)₄(H₂O)₈]·Cl₆·5.89H₂O (2), [Ln₃(Acc)₁₀(H₂O)₆]·(ClO₄)₉·4H₂O (Ln = La, (3); Nd, (4)) and [Ln₄(μ₃-OH)₄(Acc)₆(H₂O)₇(ClO₄)] ·(ClO₄)₇·11H₂O (Ln = Dy, (5); Yb, (6)), have been synthesized through the reaction of 1-amino cyclohexanel-carboxylic acid (Acc) and LnCl₃/Ln(ClO₄)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 [Ln₄(μ₃-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 Dy₂ and Dy₄ clusters exhibit slow relaxation of magnetization.