Four 1-D metal-organic polymers self-assembled from semi-flexible benzimidazole-based ligand: Syntheses, structures and fluorescent properties

Twelve Cadmium(II) Coordination Frameworks with Asymmetric Pyridinyl Triazole Carboxylate: Syntheses, Structures, and Fluorescence Properties

“…In 6 , there is no interpenetration between neighboring layers, generating large cavities with the potential for inclusion of water and methanol molecules. Furthermore, between two pyridine rings of two adjacent layers, there are π···π interactions with average center-to-center separation 3.848 Å, which result in a 3D structure. − After the removal of the free ethanol molecules, 6 is microporous and has a total potential solvent accessible volume of 18.8%, as calculated using PLATON (Table ). From a topological viewpoint, the binuclear Cd­(II) can be considered as a four-connected node, while two kinds of pmtc – ligands with different coordinated mode which can be considered as a line, are ignored.…”

“…Simultaneously, the pyridine nitrogen atoms of pmtc – ligands further link Cd­(II) ions of the neighboring chains resulting in the 2D layer framework (Figure b). Furthermore, between two adjacent interlayer triazole rings of pmtc – ligands, there are π···π interactions with average center-to-center separation 3.686 Å, − which result in the 3D structure. From the topological point of view, if the Cd­(II) are regarded as three-connected nodes, and the pmtc – ligands are viewed as three-connected nodes, the overall structure of 7 is a 2D (3,3)-connected fes network with (4·8 2 )­(4·8 2 ) topology (Figure c and Table ).…”

High Proton Conduction in Two Highly Water-Stable Lanthanide Coordination Polymers from a Triazole Multicarboxylate Ligand

“…It should be pointed out that the uncoordinated −COOH groups can serve as an efficient proton-transferring pathway. ,,, The Er–O lengths range from 2.27(3) to 2.39(3) Å, the Er–N lengths are 2.56(3) and 2.46(3) Å, and the bond angles surrounding Er­(III) vary from 66.67(1) to 147.1(1)° and are in the normal range . Neighboring Er­(III) cations are connected to form a 1D single chain by means of chelating coordination between triazole N atoms and carboxyl O atoms (Figure b), there are many hydrogen bonds in the 1D chain, and the H···O bond distances in 1 are 2.37(3) Å (145.01°) for C3–H3···O2, 2.59(3) Å (145.53°) for C4–H4A···O2, and 2.71(2) Å (153.49°) for C16–H16B···O1. − The 1D chain can be connected via the hydrogen-bond network to form a 2D structure (Figure d). In the 2D structure, there are numerous uncoordinated −COOH groups, which can also form hydrogen bonds with the coordinated water [O15–H15B···O6:1.96(4) Å (143.33°)].…”