Tricomponent Azide, Tetrazolate, and Carboxylate Cobridging Magnetic Systems: Ferromagnetic Coupling, Metamagnetism, and Single‐Chain Magnetism

Abstract

Three novel coordination polymers with azide and a bifunctional zwitterionic ligand bearing carboxylate and tetrazolate as bridging groups, [M(L)(N(3))]·xH(2)O [L=1-(carboxylatomethyl)-4-(5-tetrazolato)pyridinium, M=Cu (1, x=2), Ni (2, x=1), and Co (3, x=1)], have been synthesized and characterized by X-ray crystallography and magnetic measurements. The compounds consist of two-dimensional coordination layers in which uniform anionic chains with the unprecedented tricomponent (μ-azide)(μ-tetrazolate)(μ-carboxylate) bridges are cross-linked by cationic 1-methylenepyridinium spacers. The tricomponent bridges induce ferromagnetic interactions in all the compounds. Furthermore, this isostructural series of ferromagnetic-chain-based compounds has allowed us to observe distinct bulk properties that are dependent upon the natures of the different spin carriers: with the isotropic Cu(II) ion, 1 exhibits a paramagnetic phase of the ferromagnetic chains without long-range magnetic order above 2 K; with the weakly anisotropic Ni(II) ions, 2 displays antiferromagnetic ordering and field-induced metamagnetism without slow dynamic relaxation; and with Co(II), which has strong magnetic anisotropy due to first-order spin-orbital coupling, 3 exhibits magnetic hysteresis and slow magnetization dynamics typical of single-chain magnets.

Construction of CuII Cluster-Based Magnetic Metal–Organic Framework Derived from a V-Shaped Aromatic Dicarboxylate Ligand

“…[14] Carboxylate groups with various bridging modes and magnetic exchange pathways between metal ions have been widely used in the synthesis of MMOFs because carboxylate groups usually have the tendency to form metal-carboxylate clusters such as dinuclear, trinuclear, and even higher nuclear clusters. [15][16][17] On the other hand, gaining an understanding of network topology represents an important aspect in the realm of MOFs. [18][19][20] From the viewpoint of structural topology, polynuclear metal clusters can serve as high-connecting nodes that can also possibly form novel high-connected frameworks due to metal clusters bearing different sizes and connectivity.…”

Mixed metal CoII1−xZnIIx–organic frameworks based on chains with mixed carboxylate and azide bridges: magnetic coupling and slow relaxation

“…In this context, we performed a series of systematic studies and successfully obtained several homospin SCMs. In these compounds, Co II or Fe II ions are bridged by simultaneous azide-carboxylate, 13 azide-tetrazolate, 14 or azide-carboxylate-tetrazolate bridges, 15 and the bridges transmit ferromagnetic coupling (FO), where the formation of the particular bridging systems benefited from the use of zwitterionic pyridinium carboxylate ligands. It is worth mentioning that a family of isomorphous three-dimensional (3D) Mn II , Fe II , Co II and Ni II metal–organic frameworks (MOFs) has been obtained from different transition metal ions, azide ions and a simple zwitterionic ligand (L) ( Scheme 1 ).…”

Effects of Metal Blending in Random Bimetallic Single‐Chain Magnets: Synergetic, Antagonistic, or Innocent

“…We have successfully obtained severalh omospin SCMs in which Co II or Fe II ions being ferromagneticallyc oupledt hrough simultaneous azide-carboxylate, [14] azide-tetrazolate, [15] or azide-carboxylate-tetrazolate bridges, [16] where the formation of the bridging systems is facilitated by the use of zwitterionic pyridinium carboxylate ligands. In particular, af amily of isomorphous three-dimensional( 3D) metal-organic frameworks (MOFs) have been derived from different divalentt ransition metali ons and as imple zwitterionic ligand (L), where azidecarboxylate mixed-bridge chains are covalently linked but magnetically separated by N-methylenepyridiniumt ethers (Figure 1).…”