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5, and [Hg(L 2,3,4, ) 2 ] n , 6 and a discrete complex of [Hg(L 2,6-F ) 2 ], 7, in which L n-F ligands are N-(fluorinatedphenyl)-2pyrazinecarboxamides carrying fluorine atoms on the different positions of phenyl ring, have been synthesized and characterized. The crystal structures from X-ray diffraction reveal that all polymeric complexes have similar two-dimensional (2D) sheet windows. From a topological perspective, each metal atom can be viewed as 4-connected nodes and L n-F ligands can be considered as linkers in the formation of these 2D windows. Because of the flexibility of the ligand, fluorinated-phenyl rings as hanging groups in the windows are pointed toward the adjacent groups to generate different fluorine-involved intramolecular interactions. One of the common features in the crystal structures of these complexes is the presence of a strong tendency to form intramolecular F•••π interactions in 2D windows of the crystal structure of all polymeric complexes, except complex 3. These interactions are cooperating with weak C−H•••F and C−H•••O hydrogen bonds. Also, in the crystal structure of complexes 5 and 6, carrying three and four fluorine atoms on phenyl rings, type II F•••F synthons between adjacent rings have been observed in cooperation with F•••π interactions. Hirshfeld surface analysis also confirms that the F•••F/π contacts are predominant.

Seven inorganic coordination compounds based on HgBr2 and Ln−F ligands, in which Ln−F are N‐(fluorinated phenyl)‐2‐pyrazinecarboxamide, bearing fluorine substituent in different position on phenyl ring have been synthesized. These complexes, [HgBr2(L2−F)2]n, 1, [HgBr2L3−F]n, 2, [HgBr2L4−F]n, 3, [HgBr2L2,5−F]n, 4, [HgBr2(L2,6−F)2], 5, [HgBr2L2,3,4−F], 6, and [HgBr2L2,3,4,5−F]n, 7, are characterized in order to get precise insight into the fluorine substituent effect on the coordination structures. The crystal structure data resulting from X‐ray diffraction reveal that, in spite of the same metal, counter ion and reaction conditions, overall structural diversity is evident in all cases. Accordingly, fluorinated ligand exercise influence on not only first coordination sphere but also supramolecular architecture and overall construction. As a matter of fact, small changes in the position and number of fluorine existed on the phenyl ring direct both first and second coordination sphere around metal ion.

Key indicators: single-crystal X-ray study; T = 298 K; mean (C-C) = 0.003 Å; R factor = 0.037; wR factor = 0.093; data-to-parameter ratio = 20.8.In the title compound, [FeCl 2 (C 18

Three complexes of N-(2,5-diluorophenyl)-2-pyrazine carboxamide and ZnX2 have been synthesized. The crystal structures reveal that in all three coordination compounds, metal-bound halides have interacted with π systems through a negative electrostatic region.