Linear and nonlinear optical properties of Ln–Zn heteronuclear complexes from a Schiff base ligand containing 8-hydroxyquinoline moiety

•Nd and Yb can be efficiently sensitized by the new Schiff base ligand.•Red emission of the ligand is affected by the coordination of Eu, Tb, and Gd with Zn.•Nonlinear optical properties were obtained in these complexes.

Starting from a Schiff base ligand containing 8-hydroxyquinoline moiety, namely, 3,3′-(1E,1′E)-(propane-1,3-diylbis(azan-1-yl-1-ylidene))bis(methan-1-yl-1-ylidene) diquinolin-8-ol (H2PBIQ), five heteronuclear Ln(III)–Zn(II) complexes (([Eu2Zn(PBIQ)2(NO3)4]⋅CH2Cl2, 1), ([Tb2Zn(PBIQ)2(NO3)4]⋅CH2Cl2, 2), ([Gd2Zn(PBIQ)2(NO3)4]⋅CH2Cl2, 3), ([Nd2Zn(PBIQ)2(NO3)4]⋅CH2Cl2, 4)), and ([Yb2Zn(PBIQ)2(NO3)4]⋅CH2Cl2, 5) were obtained. Due to the low energy level resided in the excited state, the Schiff base ligand can sensitize near infrared emitting Ln(III) ions (Nd and Yb), while visible light emitting Eu and Tb ions cannot be excited. Instead, nonlinear optical properties were observed in Eu/Tb–Zn heteronuclear complexes.

Graphical abstractVis–NIR emission and nonlinear optical properties were observed in d–f heteronuclear complexes from a Schiff base ligand containing 8-hydroxyquinoline moiety.Figure optionsDownload full-size imageDownload as PowerPoint slide