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

A family of chiral 3d–4f heterometallic complexes, namely, [Zn 2 Ln( R, R -L) 2 (H 2 O) 4 ](ClO 4 ) 3 ) [Ln = Dy ( 1 ), Tb ( 3 )], [Zn 2 Ln( S, S -L) 2 (H 2 O) 4 ](ClO 4 ) 3 [Ln = Dy ( 2 ), Tb ( 4 )], [Zn 2 Ln 2 ( R, R -L) 2 (CO 3 ) 2 (NO 3 ) 2 ]·2CH 3 OH [Ln = Dy ( 5 ), Tb ( 7 )], and [Zn 2 Ln 2 ( S, S -L) 2 (CO 3 ) 2 (NO 3 ) 2 ]·2CH 3 OH [Ln = Dy ( 6 ), Tb ( 8 )] {H 2 L = 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 C 2 2 2 1, and 5 – 8 are isostructural tetranuclear clusters crystallized in chiral space group P 1. Interestingly, the adjacent [ZnLn] units within the tetranuclear cluster in 5 – 8 are bridged by two carbonate anions via in situ incorporation of CO 2 from air. Magnetic measurements indicate that complexes 1 and 3 exhibit field-induced single-molecule magnet behavior with energy barriers ( U eff ) of 22.46 and 38.70 K (or 41.87 K), respectively. Complex 5 displays typical SMM behavior with U eff = 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.