Syntheses, Structure, and Magnetic Properties of New Types of Cu(II), Co(II), and Mn(II) Organophosphonate Materials:  Three-Dimensional Frameworks and a One-Dimensional Chain Motif

The hydrothermal syntheses, structures, and magnetic properties of the Cu(II), Co(II), and Mn(II) complexes with organophosphonic acid H2O3PCH2NH2+CH2PO3H- are reported. Compound Cu3[NH2(CH2PO3)2]2 (1) crystallizes in the orthorhombic space group Pbca, with unit cell parameters a = 9.4430(10) Å, b = 9.3681(10) Å, c = 16.0755(17) Å, V = 1422.1(3) Å3, and Z = 4. The X-ray crystallographic determination reveals copper ions in two different coordination environments that are bridged by one terminal oxygen atom to form a three-dimensional framework of corner-sharing layers. Antiferromagnetic coupling between the two types of Cu units in 1 was observed at 15 K, followed by ferromagnetic ordering at 9 K. Compound Co3[NH2(CH2PO3)2]2 (2) crystallizes in the orthorhombic space group P21212 with unit cell parameters a = 10.7346(8) Å, b = 13.3704(10) Å, c = 5.3699(4) Å, V = 770.72(10) Å3, and Z = 2. All Co(II) ions are in a tetrahedral environment with both ends of the ligand bound via O atoms to adjacent Co(II) ions, thus creating tetranuclear 16-membered rings. Compound Mn{[NH2(CH2PO3H)2]2(H2O)2} (3) crystallizes in the monoclinic space group P21/n, with unit cell parameters a = 7.3668(11) Å, b = 8.1540(12) Å, c = 14.090(2) Å, β = 103.935(2)°, V = 821.4(2) Å3, and Z = 2. Four phosphate oxygen atoms and two water molecules are coordinated to the mononuclear octahedral Mn(II) ions. The amino groups are protonated and therefore do not coordinate to Mn(II). Compound 3 features a one-dimensional chain architecture stitched together by hydrogen bonds.