Family of Chiral Zn<sup>II</sup>–Ln<sup>III</sup> (Ln = Dy and Tb) Heterometallic Complexes Derived from the Amine–Phenol Ligand Showing Multifunctional Properties
He‐Rui Wen, Jun‐Jie Hu, Kai Yang, Jiali Zhang, Sui‐Jun Liu, Jinsheng Liao, Cai‐Ming Liu
Abstract
A family of chiral 3d–4f heterometallic complexes, namely, [Zn2Ln(R,R-L)2(H2O)4](ClO4)3) [Ln = Dy (1), Tb (3)], [Zn2Ln(S,S-L)2(H2O)4](ClO4)3 [Ln = Dy (2), Tb (4)], [Zn2Ln2(R,R-L)2(CO3)2(NO3)2]·2CH3OH [Ln = Dy (5), Tb (7)], and [Zn2Ln2(S,S-L)2(CO3)2(NO3)2]·2CH3OH [Ln = Dy (6), Tb (8)] {H2L = cyclohexane-1,2-diylbis(azanediyl)bis(methylene)bis(2-methoxyphenol)}, has been synthesized and characterized. Crystal structure analysis reveals that complexes 1–4 are isostructural trinuclear clusters crystallized in chiral space group C2221, and 5–8 are isostructural tetranuclear clusters crystallized in chiral space group P1. Interestingly, the adjacent [ZnLn] units within the tetranuclear cluster in 5–8 are bridged by two carbonate anions via in situ incorporation of CO2 from air. Magnetic measurements indicate that complexes 1 and 3 exhibit field-induced single-molecule magnet behavior with energy barriers (Ueff) of 22.46 and 38.70 K (or 41.87 K), respectively. Complex 5 displays typical SMM behavior with Ueff = 19.61 K under zero dc field, while for complex 7, no obvious out-of-phase signals are observed even under 2 kOe dc field, the absence of SMM behavior. The solid-state luminescence studies reveal that all complexes display the characteristic fluorescence emission of lanthanide ions. Furthermore, the Kurtz–Perry measurements reveal these complexes are potential nonlinear optical materials.