Half-sandwich lanthanide crown ether complexes with the slow relaxation of magnetization and photoluminescence behaviors

Abstract

Four half-sandwich type mononuclear lanthanide crown ether complexes with the formula [Ln(12-crown-4)(NO₃)₃] (Ln³⁺ = Dy³⁺ (1), Tb³⁺ (2), Ho³⁺ (3), and Er³⁺ (4); 12-crown-4 = 1,4,7,10-tetraoxacyclododecane) were successfully synthesized and structurally characterized. Ac magnetic susceptibility measurements reveal that dysprosium complex 1 behaves as a typical single-ion magnet, while solid state photoluminescence studies show that complexes 1 and 2 have the respective lanthanide(III) luminescence characteristics.