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Solvothermal reactions of two ligands with different geometries, derived from cyclotriphosphazene, hexakis(4-carboxylato-phenoxy)cyclotriphosphazene (H6L1) and hexakis(3-carboxylato-phenoxy)cyclotriphosphazene (H6L2) with Eu(NO3)3·6H2O in H2O/DMF under similar synthesis conditions produced three new compounds, namely, {[Eu2(L1)(H2O)4]·(H2O)4·(DMA)2}n (1), {[Eu2(L1)(H2O)8]·(H2O)2·DMA}n (2), and {[Eu2(L2)(H2O)3(DMF)]·(H2O)2·(DMA)}n (3). Compounds 1 and 2 display a 2D layer crystal structure with a distinct topological network incorporating the extended hexa-carboxylate ligand L1; in contrast, 3 has a 1D crystal structure with the highly distorted hexa-carboxylate ligand L2. In these three compounds, the ligands L1 and L2 are fully deprotonated, whose six extended carboxyl arms connect six different/same metallic nodes to generate metal–organic frameworks. The luminescence properties of three compounds have been studied at room temperature in relative detail. [ABSTRACT FROM AUTHOR]

Three new Zn(II) supramolecular complexes {[Zn(2-bpt)(tp)(H2O)](H2O)}∞ (1), [Zn(2-bpt)2(Hpa)2] (2), and [Zn(2-bpt)2(H2O)2](Hip-NO2)2 (3) have been synthesized under hydrothermal conditions by using 4-amino-3,5-bis(2-pyridyl)- 1,2,4-triazole (2-bpt) and Zn(OAc)2 with the presence of different aromatic dicarboxylic acids (H2tp = terephthalic acid, H2pa = phthalic acid, and H2ip–NO2 = 5-nitroisophthalic acid). Complex 1 shows a one-dimensional zigzag chain array, 2 represents a neutral mononuclear molecule, and 3 consists of the cationic mononuclear coordination unit and Hip-NO2 anion. Notably, in complex 3, the H2ip–NO2 ligand is partly deprotonated to balance the charge and uncoordinated to the metal center. In all three structures, the low-dimensional coordination motifs are further extended to distinct two-dimensional or three-dimensional supramolecular networks via H-bonding and/or π···π stacking interactions. Fluorescent properties for 1–3 have also been studied in solid state at room temperature. [ABSTRACT FROM AUTHOR]