title: Poly[[μ-(1-azaniumylethane-1,1-diyl)bis(hydrogen phosphonato)]sodium]: a powder X-ray diffraction study.
abstract: The title two-dimensional coordination polymer, [Na(C₂H₈NO₆P₂)]n, was characterized using powder X-ray diffraction data and its structure refined using the Rietveld method. The asymmetric unit contains one Na⁺ cation and one (1-azaniumylethane-1,1-diyl)bis(hydrogen phosphonate) anion. The central Na⁺ cation exhibits distorted octahedral coordination geometry involving two deprotonated O atoms, two hydroxy O atoms and two double-bonded O atoms of the bisphosphonate anion. Pairs of sodium-centred octahedra share edges and the pairs are in turn connected to each other by the biphosphonate anion to form a two-dimensional network parallel to the (001) plane. The polymeric layers are connected by strong O-H∙∙∙O hydrogen bonding between the hydroxy group and one of the free O atoms of the bisphosphonate anion to generate a three-dimensional network. Further stabilization of the crystal structure is achived by N-H∙∙∙O and O-H∙∙∙O hydrogen bonding.
authors.affiliation: Department of Chemistry, Atomic Energy Commission of Syria (AECS), PO Box 6091, Damascus, Syrian Arab Republic. cscientific@aec.org.sy
authors.forename: Mwaffak
authors.initials: M
authors.lastname: Rukiah
authors.forename: Thaer
authors.initials: T
authors.lastname: Assaad
mesh_terms: D004164:Diphosphonates / Q000737:chemistry*; D006860:Hydrogen Bonding; D015394:Molecular Structure; D014961:X-Ray Diffraction
chemical_list: D004164:Diphosphonates
keywords: crystal structure; powder diffraction; two-dimensional coordination polymer