C 34 H 24 Cu 2 F 8 N4O 8 , monoclinic, P21/n (no. 14), a = 13.074 ( CCDC no.: 1560964A part of the title crystal structure is shown in the figure. Tables 1 and 2 and a list of the atoms including atomic coordinates and displacement parameters. Source of materialsAn aqueous solution (10 mL) of 2,6-difluorobenzoic acid (dfbaH) (315 mg, 2.0 mmol), NaHCO 3 (160 mg, 2.0 mmol), and hexamethylenetetramine (70 mg, 0.5 mmol) was mixed with DMF/MeOH solution (10 mL) dissolving Cu(NO 3 ) 2 ·3H 2 O (300 mg, 2.2 mmol). The light blue solution was allowed to stand at room temperature to give green needle-like crystals within two weeks (yield 350 mg, 39% based on copper nitrate trihydrate). Experimental detailsHydrogen atoms were placed in calculated positions and refined as riding on their parent atoms, with C-H = 0.93 Å (aromatic), C-H = 0.96 Å (methylene), and U iso (H) = 1.2 Ueq(C). CommentCoordination polymers are of special interest because of their fascinating topological structures as well as their potential applications in many fields [3][4][5][6][7]. The self-assembly of organic molecules and metal ions construct a broad range of coordination polymers. The selection of organic ligands is a key point for rational design of targeted structures. A number of aromatic acids, especially aromatic multicarboxylates, have