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Variable-temperature powder X-ray diffraction (VT-PXRD) and thermal stability were used to characterize the coordination polymer {[Cd(HBTC)(BPP)]·1.5DMF·2H2O}n (1). From the TGA analysis, as the complex shows stepwise desolvation, the polymer was activated at different specific temperatures to get various desolvated forms and their gas sorptions, as well as luminescence, were analyzed. Complex 1 exhibits strong fluorescent emission in the solid state with the main peak at 390 nm upon excitation at 340 nm. [ABSTRACT FROM AUTHOR]

Abstract: Two new cadmium coordination polymers namely [Cd(HAmTrz–COO)4(NH4 +)2] 1; and [Cd(HAmTrz)2I2]n 2; (HAmTrz–COOH=3-amino-1,2,4-triazole-5-carboxylic acid), have been prepared based on HAmTrz–COOH as ligand. The crystal structures of 1 and 2 have been determined by single-crystal X-ray diffraction technique. In coordination-complex 1 four triazole ligands coordinate via N1 nitrogen leading to a tetrahedral geometry around cadmium ion, while in 2 the ligand prefers to coordinate to the metal in a bidentate bridging mode. The structures of both the coordination polymers can be envisaged as 3D hydrogen bonded networks. Thermogravimetric analysis shows that 2 is more stable than 1 owing to different coordination numbers of cadmium atoms. Photoluminescence properties of both the compounds have been investigated in the solid state. [Copyright &y& Elsevier]

A novel, potassium orotate (OrK) and 1,3 di (4-pyridyl) propane (dpp) based, coordination network of Zn synthesized at room temperature. The emission spectrum of the Zn-complex recorded with 290 nm excitation wavelength reveals that complex has strong luminescence with the peak maximum 380 nm (3.2627 eV) and thermal stability of 1 upto 350 °C owing to different coordination environment around zinc atoms and crystal packing. • The syn-anti μ2η1:η1 bridging carboxylate and pyridyl extended the Or-Zn-dpp moiety into 2D coordination network showing square grid sheet. • The emission spectrum of Zn-complex was recorded with 290 nm excitation wavelength which reflects that 1 has strong luminescence with peak maximum of 380 nm (3.2627 eV). A novel mixed ligand based coordination network of Zn, having formula [Zn 8 (Or) 8 (dpp) 4 (H 2 O) 8 n (1), have been engineered and synthesized at room temperature by self-assembly of potassium orotate (OrK) and 1,3 di(4-pyridyl)propane (dpp) with metal salt, Zn(OAc) 2 ·2H 2 O Single crystal X-ray structural analysis reveals that coordination sphere around Zn(II) ions, in Or-Zn-dpp moiety, having different atomic arrangement with distorted square pyramidal geometry. The syn-anti μ2η1:η1 bridging carboxylate and pyridyl moieties extended the Or-Zn-dpp skeleton into 2D coordination network showing square grid sheet. The emission spectrum of Zn-complex was recorded with 290 nm excitation wavelength which reflects that 1 has strong luminescence with peak maximum of 380 nm (3.2627 eV) and is a result of the n – π * and π – π * transitions of H 3 Or and dpp ligand. Thermogravimetric analysis shows that when the coordinated water molecule completely comes out from the complex around 320 °C, the dehydrated forms steadily starts to degrade, and the complete decomposition is observed above 350 °C. [ABSTRACT FROM AUTHOR]