A two-dimensional Ni(II) coordination polymer built of 4-(1,2,4-triazol-4-yl)phenylphosphonate: Synthesis, structure and ferromagnetic magnetic property

• A two-dimensional Ni(II) coordination polymer containing isolated 1D Ni(II) chains.
• Reversible dehydration and rehydration induced phase transformation.
• Ferromagnetic coupling mediated in the chain.
• Theoretical calculation reveals the exchange path.

Hydrothermal reaction of NiCl2 and H2ptz ligand leads to the formation of a two-dimensional Ni(II) coordination polymer, named as [Ni(Hptz)(μ2-Cl)]·2H2O (1, H2ptz = 4-(1,2,4-triazol-4-yl)phenylphosphonate acid), which contains 1D Ni(II) chain structure with a Ni⋯Ni distance of 3.704 Å, and shows a (3,6)-connected net with a Schläfli symbol of (3.62)2(34.42.84.95). Magnetic study reveals a ferromagnetic coupling mediated in the chain structure with a fitted J value of 5.0 K. Furthermore, theoretical calculation suggests that the exchange path of Ni–Cl–Ni with spin orbit of dxz–pz–dxz contributes mainly to the ferromagnetic coupling.

A two-dimensional Ni(II) coordination polymer which contains 1D Ni(II) chain structure has been synthesized. Magnetic study reveals a ferromagnetic coupling, and theoretical calculation suggests that the exchange pathway of Ni–Cl–Ni with spin orbit of dxz–pz–dxz contributes mainly to the ferromagnetic coupling.Figure optionsDownload as PowerPoint slide