A mixed metal phosphate incorporating isonicotinate ligand: synthesis, crystal structure, and magnetic properties of Cu(HINT)(VO2)(PO4)

摘要

A mixed metal phosphate incorporating isonicotinate ligand, Cu(HINT)(VO2)(PO4), was hydrothermally synthesized and characterized by single-crystal X-ray diffraction and magnetic susceptibility. This compound crystallizes in the monoclinic space group C2/c with cell parameters a = 22.033(1)Angstrom, b = 6.2986(3) Angstrom,c = 16.0202(9) Angstrom, beta = 121.001 (1), and Z = 8. The structure consists of two-dimensional neutral sheets of CuVO2(PO4) with the dipolar isonicotinate ligand being coordinated to Cu ions as a pendent group. Adjacent sheets are connected by hydrogen bonding. Each sheet consists of infinite chains of CuO6 octahedra sharing trans edges which are connected by double chains of vanadyl(V) phosphate via corner sharing. Magnetic study results indicate the presence of intrachain ferromagnetic coupling between Cu ions. The magnetic exchange parameter was estimated as 2J/ k = 51.83 K based on an S = 1/2 equally spaced ferromagnetic chain model. (C) 2004 Elsevier Inc. All rights reserved.