A novel amide type ligand benzyl-N,N-bis[(2'-furfurylaminoformyl)phenoxyl)ethyl]-amine (L) has been designed and applied for the self-assembly generation of homodinuclear lanthanide coordination compounds [Ln2(μ2-L)2(NO3)6(EtOH)2] [Ln = Eu (1), Tb (2), and Gd (3)] and a heterodinuclear derivative [EuTb(μ2-L)2(NO3)6(EtOH)2] (4). All the complexes have been characterized by the X-ray single-crystal diffraction analyses. They are isostructural, crystallize in a monoclinic space group P21/c, and form [2 + 2] rectangular macrocycle structures. Compound 4 is the first example of a [2 + 2] rectangular macrocycle heterodinuclear EuTb complex assembled from an amide type ligand. In 4, the discrete 0D dimeric [EuTb(μ2-L)2(NO3)6(EtOH)2] units are extended, via the multiple N-H···O hydrogen bonds, into a 2D supramolecular network that has been topologically classified as a uninodal 4-connected underlying net with the sql [Shubnikov tetragonal plane net] topology. The triplet state ((3)ππ*) of L studied by the Gd(III) complex 3 demonstrated that the ligand beautifully populates Tb(III) emission (Φ = 52%), whereas the corresponding Eu(III) derivative 1 shows weak luminescence efficiency (Φ = 0.7%) because the triplet state of L has a poor match with (5)D1 energy level of Eu(III). Furthermore, the photoluminescent properties of heterodinuclear complex 4 have been compared with those of the analogous homodinuclear compounds. The quantum yield and lifetime measurements prove that energy transfer from Tb(III) to Eu(III) is being achieved, namely, that the Tb(III) center is also acting to sensitize the Eu(III) and enhancing Eu(III) emission in 4.

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To confirm how different anions influence sup-ramolecular self-assembly of lanthanide-organic frameworks (LnOFs) as well as their luminescent properties, a new flexible achiral tripodal ligand, 1,1,1-tris-{[(2'-benzylaminoformyl)phenoxyl]methyl}ethane (L) and the LnOFs {[EuL(NO(3))(3)]·1.5CHCl(3)}(n) and [EuL(pic)(3)](n) have been designed and assembled. In the two LnOFs, {[EuL(NO(3))(3)]·1.5CHCl(3)}(n) demonstrates an unprecedented chiral noninterpenetrated two-dimensional (2D) honeycomblike (6,3) (hcb, Schläfli symbol 6(3), vertex symbol 6·6·6) topological network, and [EuL(pic)(3)](n) confirms an unusual chiral LnOF with three-dimensional (3D) (10,3)-a (srs, SrSi(2), Schläfli symbol 10(3), vertex symbol 10(2)·10(4)·10(4)) topological framework. Also the anion-induced structures and energy transfer processes in the luminescence behavior of the two LnOFs were discussed in detail.

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