Anion-Dependent Assembly of Four Sensitized Near-Infrared Luminescent Heteronuclear Zn^II–Yb^III Schiff Base Complexes from a Trinuclear Zn^II Complex

Abstract

Four anion-dependent 0D Zn(II)-Yb(III) heterometallic Schiff base complexes, [YbZn2L2(OAc)4]·ClO4 (2), YbZnL2(NO3)3 (3), [(YbL)2(H2O)Cl(OAc)]2·[ZnCl4]2 (4), and YbZnL(OAc)4 (5), were assembled through central metal substitution or reconstruction from homotrinuclear Zn(II) complex {[(Zn(OAc)(H2O)L]2Zn}(ClO4)2·4H2O [1; HL = 2-ethoxy-6-[(pyridin-2-ylmethylimino)methyl]phenol] with different Yb(III)X3 salts [X = ClO4 (2), NO3 (3), Cl (4), and OAc (5)], in which the Zn(II)-sensitized near-infrared luminescent performances in the four complexes 2-5 are closely related to their structural models.

Four New Families of Polynuclear Zn-Ln Coordination Clusters. Synthetic, Topological, Magnetic, and Luminescent Aspects

“…Since then, the synthesis of Zn II /Ln III CCs has gained remarkable attention, (a) for magnetic behavior that can be explained due to the diamagnetic character of the Zn II ion, which has also been shown to enhance the energy barrier in Zn II /Dy III SMMs; and (b) because Eu III and Tb III are attractive luminescent centers, due to their long-lived 5 D 0 and 5 D 4 excited states and the accompanying large Stokes’ shifts. In addition, the combination with Zn II ions may produce species with enhanced luminescent properties via f–d energy transfer; a plethora of such mixed metal species have been reported and the magnetic and luminescent properties of such compounds have been very well investigated. ,− …”

Two Schiff base ligands for distinguishing ZnII/CdII sensing—effect of substituent on fluorescent sensing

“…The Schiff-base ligand 2-ethoxy-6((pyridin-2-ylmethylimino)methyl)phenol (HL 1 ) was synthesized according to corresponding reference. 13 2-((Pyridin-2-ylmethylimino)methyl)phenol (HL 2 ) was prepared according to related reference. 14 Synthesis of compounds 1-4 [Zn 4 (L 1 )(L 1 0 )Cl 5 ] (1).…”

Family of Chiral ZnII–LnIII (Ln = Dy and Tb) Heterometallic Complexes Derived from the Amine–Phenol Ligand Showing Multifunctional Properties

“…Recently, 3d–4f heterometallic complexes have attracted increasing attentions due to their extraordinary and fascinating structures, − as well as many potential applications in molecular magnetism, , optical materials, − and catalysis. − After the first example of 3d–4f heterometallic complex was reported, , more 3d–4f heterometallic complexes have been synthesized and investigated. − Compared with the other 3d–4f complexes, Zn II -Ln III complexes have aroused more remarkable attention due to the following reasons: (a) Diamagnetic Zn II ions can increase the negative charge on the bridged oxygen center between the diamagnetic metal ion and the 4f metal ion to stabilize the ground states of the lanthanide ions, resulting in the enhancement of energy barriers of such complexes; and (b) Ln III ions such as Eu III and Tb III are good luminescent centers, and the combination of Ln III and Zn II ions may promote luminescent properties via f–d energy transfer . Many Zn II –Ln III heterometallic complexes have been reported, and their magnetic and luminescent properties have been well investigated. − …”