Synthesis, Structure, and Magnetic Characterization of a Series of Iron(II) Coordination Frameworks with 2, 6-Bis(1, 2,4-triazole-4-yl)pyridine

Based on the bis‐triazole ligand 2, 6‐bis(1, 2,4‐triazole‐4‐yl)pyridine (L), the triazole‐iron(II) complexes [Fe(L)2(dca)2(H2O)2]·2H2O (1) (Nadca = sodium dicyanamide), {[Fe(μ2‐L)2(H2O)2]Cl2}n (2), and {[Fe(μ2‐L)2(H2O)2](ClO4)2·L·H2O}n (3) were isolated by solvent diffusion methods. When iron(II) salts and Nadca were used, compound 1 was isolated, which contains mononuclear Fe(L)2(dca)2(H2O)2 units. When FeCl2 or FeClO4 were used, one‐dimensional (1D) cation iron(II) chains (2) and two‐dimensional (2D) cation iron(II) networks (3) were isolated indicating anion directing structural diversity. Moreover, variable‐temperature magnetic susceptibility data of 1–3 were recorded in the temperature range 2–300 K. The magnetic curve of complex 2 was fitted by using the classical spin Heisenberg chain model indicating anti‐ferromagnetic interactions (J = –5.31 cm–1). Obviously complexes 1–3 show no detectable thermal spin crossover behaviors, the lack of spin‐crossover behavior may be correlated with FeN4O2 coordination spheres in 1–3.