Currently, the design and synthesis of metal-organic frameworks (MOFs) attract broad attention because of the interesting structural architectures and topological features which have a key role in the final behavior of their application [1]. In order to construct porous compound networks, the common strategy is employed based on the suited selection of organic linkers and metal ions that affect the final topology of the clustered networks [2, 3]. In this work, to obtain a new topological structure of a zinc-1,3,5-benzentricarboxylate (Zn-BTC) MOF, we choose the various synthetic methods in the presence of different solvents and ratios of the Zn:BTC reagents. Herein, we report the synthesis and characterization of a new Zn-BTC MOF (FUM-181) with the heptanodal topology. The single-crystal X-ray diffraction (SCXRD) reveals that FUM-181 crystallizes in the monoclinic space group P2 1 / c. The crystal structure of FUM-181 consists of seven independent Zn 2+ centers, four topologically different kinds of BTC 3- groups (BTC-1, BTC- 2, BTC-3, and BTC-4), four H 2 O, two -OH groups, and three coordinated DMF molecules in the asymmetric unit. A precise examination of FUM-181 demonstrates that it is a three-dimensional network with complicated and unusual pore structures. Furthermore, a detailed theoretical study has been carried out on the adsorption of CO 2 and CH 4 in this MOF at 298, 303, 318, and 333 K and 1-50 bar. The theoretical gas adsorption measurement predicts that FUM-181 has a superior performance in CH 4 gas adsorption compared to CO 2 . It is worth mentioning, Hong et. al have recently reported a new hexanodal zinc-BTC MOF with high CO 2 gas adsorption [4]. Interestingly, the changing gas adsorption behavior can be observed in our reported Zn-BTC MOF by changing the hexanodal to heptanodal topology

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