Synthesis and characterization of two metal phosphonates with 3D structures: Cui2CuII[(3-C5H4N)CH(OH)PO3]2 and Zn[(3-C5H4N)CH(OH)PO3]

Abstract

Two novel phosphonate compounds, Cu^I₂Cu^II[(3-C₅H₄N)CH(OH)PO₃]₂ (1) and Zn[(3-C₅H₄N)CH(OH)PO₃] (2), have been synthesized by solvothermal reactions of the corresponding metal salts with [hydroxy(3-pyridyl)methyl]phosphonic acid. Compound 1 contains inorganic chains made up of Cu^IIO₄ planes and CPO₃ tetrahedra through corner sharing. These chains are connected by Cu^ION units through pyridine rings, forming a 3D open framework structure. Compound 2 adopts a new type of pillared layered structure. The inorganic layer contains 8- and 16-membered rings made up of ZnO₃N and CPO₃ tetrahedra. Pyridine rings are fixed between the inorganic layers through covalent bonds. The magnetic study shows that weak ferromagnetic interactions are mediated between magnetic centers in compound 1.