Synthesis, Structure and Thermal Behavior of a New Coordination Polymer Based on Mixed Pyrazine-2-carboxylate and Oxalate Ligands

Abstract

A new 4d–4f coordination polymer, [AgGd(pyzc)2(ox)·H2O)] (1) [pyzc = Pyrazine-2-carboxylate, ox = oxalate] has been successfully synthesized under hydrothermal conditions and structurally determined by single-crystal X-ray diffraction, and characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis and power X-ray diffraction. Single-crystal X-ray analysis reveals that it crystallizes in the monoclinic space group P2 1 /c with a = 10.0746(1) A, b = 18.642(1) A, c = 8.0525(2) A, β = 112.470(1)°, Mr = 617.34, Z = 4, V = 1505.6(2) A3, μ = 5.732, F(000) = 1164. The Gd(III) ion is nine-coordinated by two O-donors and two N-donors of two different chelating pyzc ligands, four O-donors of two different chelating oxalate ligands, and one O-donor of another carboxylate group of one pyzc ligand. The compound represents a 3D microporous polymeric network constructed by gadolinium–oxalate chains and Ag-pyzc subunits. The compound [AgGd(pyzc)2(ox)·H2O)] (1) Pyrazine-2-carboxylate (pyzc), oxalate (ox) exhibits a new 4d–4f three-dimensional (3D) heterometallic polymeric network that is assembled from the gadolinium–oxalate chains and Ag-pyzc subunits.