A family of acetato-diphenoxo triply bridged dimetallic Zn(II)Ln(III) complexes: SMM behavior and Luminescent properties

作者：Oyarzabal Ltziar; Artetxe Benat; Rodriguez Dieguez Antonio; Angel Garcia Jose; Manuel Seco Jose; Colacio Enrique

来源：Dalton Transactions, 2016, 45(23): 9712-9726.

DOI：10.1039/c6dt01327a

Eleven dimetallic Zn-II-Ln(III) complexes of the general formula [Zn(mu-L)(mu-OAc)Ln(NO3)(2)].CH3CN (Ln(III) = Pr (1), Nd (2), Sm (3), Eu (4), Gd (5), Tb (6), Dy (7), Ho (8), Er (9), Tm (10), Yb (11)) have been prepared in a one-pot reaction from the compartmental ligand N,N'-dimethyl-N,N'-bis(2-hydroxy-3-formyl-5-bromo-benzyl)ethylenediamine (H2L). In all these complexes, the Zn-II ions occupy the internal N2O2 site whereas the Ln(III) ions show preference for the 04 external site. Both metallic ions are bridged by an acetate bridge, giving rise to triple mixed diphenoxido/acetate bridged Zn(II)Ln(III) compounds. The Nd, Dy, Er and Yb complexes exhibit field induced single-ion magnet (SIM) behaviour, with U-eff values ranging from 14.12 to 41.55 K. The Er complex shows two relaxation processes, but only the second relaxation process with an energy barrier of 21.0 K has been characterized. The chromophoric L2- ligand is able to act as an "antenna" group, sensitizing the near-infrared (NIR) Nd-III and Yb-III-based luminescence in complexes 2 and 11 and therefore, both compounds can be considered as magneto-luminescent materials. In addition, the Sm-III, Eu-III and Tb-III derivatives exhibit characteristic emissions in the visible region.

• 出版日期2016-6-21