Toward tuning the bulk magnetic behaviors of metal-azido materials by organic pillars

Two novel 3D species with the pillared-layer structure were reported, in which the same Cu(II)-azido two-dimensional (2D) layers are pillared by two similar organic linkers of different length that influences the bulk magnetic behaviors. The 2D layer, with an unprecedented metal-azido bridging topology, was built through symmetric μ-1,1 and asymmetric μ-1,1,3 azides, both of which propagate ferromagnetic interactions. The change in the linker length can effectively tune the interlayer antiferromagnetic interactions, and hence the critical fields for the metamagnetic transitions. X-ray crystallographic analysis showed that both complexes are 3D coordination polymers, in which 2D inorganic layers of Cu(II) ions and azido ions are interlinked by organic ligands. Investigations along this line will help to understand and control the magnetic interactions between low-dimensional motifs at the supramolecular level, contributing to the rational design of molecular magnets.