Mixed anion-induced Salen-based Zn2Ln3 (Ln=Nd, Yb or Er) complexes with near-infrared (NIR) luminescent properties
作者:Heini Feng、Zhao Zhang、Weixu Feng、Peiyang Su、Xingqiang Lü、Daidi Fan、Wai-Kwok Wong、Richard A. Jones、Chengyong Su
DOI:10.1016/j.inoche.2014.02.034
日期:2014.5
A series of mixed anion-induced Zn(2)Ln(3) complexes [Zn-2(L)(3)Cl-2(mu(2)-OH)(mu(3)-OH)(2)Ln(3)(N-3)(2)] (Ln = La, 1; Ln = Nd, 2; Ln = Yb, 3; Ln = Er, 4 or Ln = Gd, 5) have been obtained by the self-assembly of the precursor [Zn(L)(MeCN)] (H2L = N,N'-bis(3-methoxy-salicylidene)cyclohexane-1,2-diamine) with LnCl(3).6H(2)O (Ln = La, Nd, Yb, Er or Gd) and NaN3 in alcohol-containing solutions. In these reactions, transmetallation of the partial precursor leads to the coexistence of two Zn2+ ions and one Ln(3+) ion in the inner cis-N2O2 core and the other two Ln(3+) ions in the outer N2O2 moieties of three deprotonated ligands. Photophysical studies suggest that the characteristic near-infrared (NIR) luminescence of Nd3+ and Yb3+ ions is sensitized through both the excited singlet (LC)-L-1 and triplet (LC)-L-3 states of the depronated ligand (L)(2-) despite the luminescent quenching with three OH oscillators arround the Ln(3+) ions. (C) 2014 Elsevier B.V. All rights reserved.