The synthesis and structural characterization of a hydrated high-spin iron(II) complex [Fe(4-qtrz)2(tcm)2(H2O)2] are reported where 4-qtrz = 4-quinolin-3-yl-4H-1,2,4-triazole and tcm = tricyanomethide. The complex was prepared solvothermally and crystallizes in the triclinic space group P-1 with Z = 1, a = 8.5221(3) Å, b = 8.9343(5) Å, c = 10.0081(5) Å, α = 85.147(2) °, β = 77.166(2) °, γ = 83.784(2) °. The complex is centrosymmetric, with mutually trans pairs of water molecules, of tcm, and monodentate 4-qtrz coordinated via the triazole unit and a combination of O–HN and C–HN hydrogen bonds, forming a three-dimensional framework structure in which the shortest FeFe distance is 8.5221(3) Å. An analysis of non-covalent interactions was conducted through reduced density gradient, quantum theory of atoms in molecules and natural bond orbitals. Accordingly, the important contributions of several intra- and inter-molecular hydrogen bonds stabilize the supramolecular structure. The hydrogen bonds occur by electron transfer from the tricyanomethanide nitrogen lone pairs to σ* orbitals in the triazole, quinoline and water moieties. Other hydrogen bonds are attributed to π(CN) → σ*, in triazole and quinoline, transfer. Additionally, a set of ππ* interactions between cyano groups (CNCN), π(phenyl of quinoline)π*(CN), and π[CC of C(CN)3] to π*(phenyl of quinoline) were also observed.

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