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Effective incorporation of multiple types of ligands in a given coordination structure provides structural complexity and functional diversity to the resultant coordination‐driven assembly. One of the most widely used synthetic approaches is the utilization of the molecular symmetry principle to combine multiple ligands and specific metallic centers in a preferred manner. The variation of metal ions can be helpful to understand the importance of symmetry for the generation of structurally hierarchical supramolecular platforms. We describe the synthesis and characterization of isostructural supramolecular helicates, [M8(PDA)6(AIP)3(DMF)6−x(H2O)x] (M=Ni (1), Co (2), and Mn (3); PDA=2,6‐pyridinedicarboxylate; AIP=5‐aminoisophthalate; x=0 for 1, and x=4 for 2 and 3). The effect of metal variation on the formation of supramolecular helicates and their solid‐state crystal packing are discussed. Despite the disparity in the ionic radii and distinct coordination‐geometry preferences of Co2+, Ni2+, and Mn2+, all metal centers engaged in the assembly with the heteroleptic ligands in the same manner to form isostructural supramolecular helicates. Metal ions in action! The synthesis and characterization of isostructural supramolecular helicates, [M8(PDA)6(AIP)3(DMF)6−x(H2O)x] [M=Ni (1), Co (2), and Mn (3); PDA=2,6‐pyridinedicarboxylate; AIP=5‐aminoisophthalate; x=0 for 1, and x=4 for 2 and 3] are reported. Despite the disparity in the ionic radii and distinct coordination geometry preferences of Co2+, Ni2+, and Mn2+, all metal centers engaged in the assembly with the heteroleptic ligands in the same manner to form isostructural supramolecular helicates. [ABSTRACT FROM AUTHOR]

This paper explores the thermal and catalytic pyrolysis of HFC-134a over γ-Al2O3 calcined at temperatures of 550 °C (A550), 650 °C (A650), 750 °C (A750), and 850 °C (A850). The physicochemical properties of catalysts were studied through thermogravimetric analysis (TGA), Brunauer–Emmett–Teller equation for nitrogen physisorption analysis (BET), X-ray diffraction (XRD), and temperature-programmed desorption of ammonia (NH3-TPD). The non-catalytic pyrolysis of HFC-134a showed less than 15% decomposition of HFC-134a. Catalysts increased the decomposition as A650 revealed the highest decomposition efficiency by decomposing more than 95% HFC-134a for 8 h followed by A750, A850, and A550. The larger surface area and pore volume paired with a low amount of strong acidic sites were considered as the main contributors to the comparatively longer catalytic activity of A650. [ABSTRACT FROM AUTHOR]