Three-Dimensional 3d−4f Heterometallic Coordination Polymers: \nSynthesis, Structures, and Magnetic Properties

Abstract

Three new 3d−4f heterometallic coordination polymers, [Ln₂(H₂O)₄M₂(H₂O)₂(QA)₅]·<i>n</i>H₂O (H₂QA<b> =</b> quinolinic acid;\nLn = Gd, M = Ni, <i>n</i> = 7 (<b>1</b>); Ln = Gd, M = Co, <i>n</i> = 6.5 (<b>2</b>); Ln = Dy, M = Co, <i>n</i> = 6.5 (<b>3</b>)), have been\nsynthesized through hydrothermal pretreatment and cooling-down crystallization. These compounds possess the\nisostructural 3D frameworks with 1D chairlike channels along the <i>c</i> axis, which are occupied by noncoordinating\nwater molecules. Crystal data: for <b>1</b>, C₃₅H₄₁Gd₂Ni₂N₅O₃₃, orthorhombic, space group <i>Pna</i>2₁, with <i>a</i> = 28.567(6) Å,\n<i>b</i> = 14.498(3) Å, <i>c</i> = 12.250(2) Å, and <i>Z</i> = 4; for <b>2</b>, C₃₅H₄₀Gd₂Co₂N₅O_32.5, orthorhombic, space group <i>Pna</i>2₁, with\n<i>a</i> = 28.843(3) Å, <i>b</i> = 14.4325(13) Å, <i>c</i> = 12.2275(9) Å, and <i>Z</i> = 4; for <b>3</b>, C₃₅H₄₀Dy₂Co₂N₅O_32.5, orthorhombic,\nspace group <i>Pna</i>2₁, with <i>a</i> = 28.8471(14) Å, <i>b</i> = 14.4534(10) Å, <i>c</i> = 12.2520(7) Å, and <i>Z</i> = 4. The magnetic\nbehaviors for the three compounds have been investigated.