Zinc diphosphonates templated by organic amines:: Syntheses and characterizations of [NH3(CH2)2NH3]Zn(hedpH2)2•2H2O and [NH3(CH2)nNH3]Zn2(hedpH)2•2H2O (n=4, 5, 6) (hedp=1-hydroxyethylidenediphosphonate)

Four new zinc diphosphonate compounds with formulas [NH3(CH2)(2)NH3]Zn(hedpH(2))(2). 2H(2)O, 1, [NH3(CH2)(n-) NH3]Zn-2(hedpH)(2). 2H(2)O, (n = 4, 2; n = 5, 3; n = 6, 4) (hedp = 1-hydroxyethylidenediphosphonate) have been synthesized under hydrothermal conditions at 110 degreesC and in the presence of alkylenediamines NH2(CH2)(n)NH2 (n = 2, 4, 5, 6). Crystallographic data for 1: monoclinic, space group C2/c, a = 24.742205), b = 5.2889(2), c = 16.0338(2) Angstrom,beta = 117.903(1)degrees, V 1856.17(18) Angstrom (3), Z = 4; 2: monoclinic, space group P2(1/n), a = 5.4970(3), b = 12.1041(6), c = 16.2814(12) Angstrom,beta = 98.619(5)degrees, V = 1071.07(11) Angstrom (3), Z = 2; 3: monoclinic, space group P2(1)/n, a = 5.5251(2), b = 12.5968(3), c = 16.1705(5) Angstrom,beta = 99.182(1)degrees, V = 1111.02(6) Angstrom (3), Z = 2; 4: triclinic, space group P-1, a = 5.4785(2), b = 14.1940(5), c = 16.0682(6) Angstrom, alpha = 81.982(2)degrees, beta = 89.435(2)degrees, gamma = 79.679(2)degrees, V = 1217.11(8) Angstrom (3), Z = 2. In compound 1, two of the phosphonate oxygens are protonated. The metal ions are bridged by the hedpH(2)(2-) groups through three of the remaining four phosphonate oxygens, forming a one-dimensional infinite chain. The protonated ethylenediamines locate between the chains in the lattice. In compounds 2-4, only one phosphonate oxygen is protonated. Compounds 2 and 3 have a similar three-dimensional open-network structure composed of {Zn-2(hedpH)(2)}(n) double chains with strong hydrogen bonding interactions between them, thus generating channels along the [100] direction. The protonated diamines and water molecules reside in the channels. Compound 4 contains two types of {Zn-2(hedpH)(2)}(n) double chains which are held together by strong hydrogen bonds, forming a two-dimensional network. The interlayer spaces are occupied by the [NH3(CH2)(6)NH3](2+) cations and water molecules. The significant difference between structures 2-4 is also featured Z by the coordination geometries of the zinc atoms. The geometries of those in 2 can be described as distorted octahedral, and those in 3 as distorted square pyramidal. In 4, two independent zinc atoms are found, each with a distorted octahedral and a tetrahedral geometry, respectively.