Three-dimensional networks based on trinuclear motifs with tricomponent azide-carboxylate-tetrazolate cobridges: Synthesis, structure and magnetic properties

摘要

Two 3D coordination polymers of Mn ~(II) with azide and bifunctional zwitterionic ligands bearing both carboxylate and tetrazolate groups, 1-(carboxylatomethyl)-3-(5-tetrazolato)pyridinium (L ~1) and 1-(carboxylatoethyl)-4-(5-tetrazolato)pyridinium (L ~2), were synthesized, and structurally and magnetically characterized. They are formulated as [Mn _3(L ~1) _2(N ~3) _4(H _2O) _2] _n·4nH _2O (1) and [Mn _3(L _2) _2(N _3) _4(H _2O) _3] _n·3.5nH _2O (2). In both compounds, octahedral Mn ~(II) ions are linked by the mixed (μ _2-EO-N _3)(μ _2-syn,syn-COO) (μ _2-N _2,N _3-CN _4) (CN _4 = tetrazolate and EO = end-on) triple bridges to give anionic linear trinuclear motifs. The motifs are connected through EE-N _3 (EE = end-to-end) bridges to give layers and chains in 1 and 2, respectively, and the cationic pyridinium spacers serve to interlink the layers or chains into three-dimensional frameworks with the α-Po and CdSO _4-type topology, respectively. Magnetic studies demonstrated that the magnetic interactions within and between the trinuclear motifs, through the tricomponent and EE-N _3 bridges, respectively, are both antiferromagnetic in both compounds.