Synthesis, Structures, and Magnetic Properties of New Thiocyanato Coordination Polymers with 4-(3-Phenylpropyl) pyridine as Ligand

The reaction of different metal salts with 4-(3-phenylpropyl)pyridine (ppp) lead to the formation of compounds of composition M(NCS)(2)(ppp)(4) [M = Mn (Mn-1); Fe (Fe-1), Ni (Ni-1); Cd (Cd-1)], M(NCS)(2)(ppp)(2)(H2O)(2) [M = Mn (Mn-2); Ni (Ni-2)] and [M(NCS)(2)(ppp)(2)](n) [M = Mn (Mn-3); Ni (Ni-3); Cd (Cd-3)]. On heating compounds M-1 decompose without the formation of any ppp deficient intermediate. In contrast, on heating, Ni-2 transforms into a compound of composition M(NCS)(2)(ppp)(2) that does not correspond to Ni-3. Unfortunately, this compound is of low crystallinity and therefore, its structure cannot be determined. The crystal structures of compounds M-1 and M-2 consist of discrete complexes, in which the metal cations are octahedrally coordinated. In compounds M-3 the metal cations are linked by pairs of -1,3-bridging anions into chains. IR spectroscopic investigations show, that the value of the asymmetric CN stretching vibration depend on the coordination mode of the anionic ligand as well as on the nature of the metal cation. Magnetic measurements reveal that Ni-3 shows only Curie-Weiss behavior without any magnetic anomaly. A similar behavior is also found for Ni-3. Comparison of the magnetic properties of Ni-3 with those of similar compounds indicates that the magnetic properties are only minor influenced by the Co-ligand.