Syntheses, structures and photoluminescent properties of a series of Ag(I) coordination architectures based on 2,4-diamino-6-methyl-1,3,5-triazine and dicarboxylates: from a 0D discrete molecule to a 3D infinite network

Five mixed-ligand Ag(I) coordination complexes (CCs), namely, [Ag-2(dmt)(2)(suc)center dot H2O](n) (1), [Ag-2(dmt)(2)(suc)(H2O)center dot 0.5H(2)O] (2), [Ag-2(dmt)(2)(glu)](n) (3), [Ag-2(dmt)(2)(adip)](n) (4), and [Ag-2(dmt)(2)(tpa)](n) (5) (dmt = 2,4-diamino-6-methyl-1,3,5-triazine, H(2)suc = succinic acid, H(2)glu = glutaric acid, H(2)adip = adipic acid, H(2)tpa = terephthalic acid), have been synthesized through a one-pot ultrasonic reaction of AgNO3, dmt and different dicarboxylates and characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. Complexes 1 and 2 formed in different solvent systems (methanol/acetonitrile for 1 and methanol/ethanol for 2) exhibit a two-dimensional (2D) sheet and a zero-dimensional (0D) tetranuclear motif, respectively. Different solvent systems influence the coordination modes (mu(2)-N,N' for 1 and mu(1)-N for 2) of dmt and the conformations (anti for 1 and gauche for 2) of the suc anion; as a result, two diverse structures are produced. Complex 3 is a one-dimensional (1D) chain structure running along the a axis constructed from the [Ag-2(mu(1)-dmt)(2)] subunit and the gauche-gauche mu 5-eta(1):eta(1):eta(1):eta(2) glu ligand. Similarly, complex 4 is also a 1D chain structure, but the adip ligand adopts an anti-anti-anti conformation to link the [Ag-2(mu(1)-dmt)(2)] subunit to complete the 1D chain. Complex 5 is a complicated 3D framework built from a tetrahedral Ag(I) center, a quadridentate tpa and an angular bidentate dmt ligand which can be simplified as a new (2,4,4)-connected 3-nodal net with the Schlafli symbol of {4.8(4).12}(2){4(2).8(2).10(2)}{8}(2). The results show that the dicarboxylate and the solvent system play crucial roles in the formation of the resulting structures. Additionally, results about thermogravimetric curves and photoluminescence spectra were discussed.