A Deep Insight into the Photoluminescence Properties of Schiff Base Cd-II and Zn-II Complexes

作者：Majumder Ishani; Chakraborty Prateeti^*; Dasgupta Sanchari; Massera Chiara; Escudero Daniel^*; Das Debasis^*

来源：Inorganic Chemistry, 2017, 56(21): 12893-12901.

DOI：10.1021/acs.inorgchem.7b01692

A tridentate N,N,O donor ligand 2,4-dichloro-2-[(2-piperazine-4-yl-ethylimino)-methyl]-phenol (HL) was designed, and eight new Zn-II and Cd-II complexes, namely, [Zn(LH)(SCN)(2)] (1), [Zn(LH)(N-3)(2)] (2), [Zn(LH)(NO2)(2)] (3), [Zn(LH)(dca)(OAc)] (4), [Cd-2(LH)(2)(SCN)(4)] (5), [Cd(LH)(N-3)(2)] (6), [Cd(LH)(NO2)(2)] (7), and [Cd(LH)(dca)(OAc)] (8) [where dca = dicyanamide anion] were synthesized. Five of them (1, 2, 4, 5, 7) were structurally characterized through single-crystal X-ray diffraction analysis. H-Bonding interactions are found to be the major stabilizing factor for crystallization in the solid state. Experimental and computational studies were performed in cooperation to provide a rationalization of the photoluminescence properties of those complexes. The quantum yields are anion-dependent, with enhanced efficiencies in the following order: LH < Cd-SCN(5) < Cd-dca(8) < Cd-N-3(6) < Cd-NO2(7) < Zn-dca(4) < Zn-N-3(2) < ZnNO2(3) < ZnSCN(1). By using quantum chemical calculations we rationalized the above trends. Moreover, the diverse lifetimes observed for those eight complexes were also quantitatively explained by considering the subtle competition between different photo-deactivation pathways.

• 出版日期2017-11-6