title: Hydro-thermal synthesis and crystal structure of a new lanthanum(III) coordination polymer with fumaric acid.
abstract: The title compound, poly[di-aqua-tris-(μ4-but-2-enedioato)(μ2-but-2-enedioic acid)dilanthanum(III)], [La2(C4H2O4)3(C4H4O4)(H2O)2] n , was synthesized by the reaction of lanthanum chloride penta-hydrate with fumaric acid under hydro-thermal conditions. The asymmetric unit comprises an La(III) cation, one and a half fumarate dianions (L (2-)), one a half-mol-ecule of fumaric acid (H2 L) and one coordinated water mol-ecule. Each La(III) cation has the same nine-coordinate environment and is surrounded by eight O atoms from seven distinct fumarate moieties, including one proton-ated fumarate unit and one water mol-ecule in a distorted tricapped trigonal-prismatic environment. The LaO8(H2O) polyhedra centres are edge-shared through three carboxyl-ate bridges of the fumarate ligand, forming chains in three dimensions to construct the MOF. The crystal structure is stabilized by O-H⋯O hydrogen-bond inter-actions between the coordin-ated water mol-ecule and the carboxyl-ate O atoms, and also between oxygen atoms of fumaric acid.
authors.affiliation: Unité de Recherche de Chimie de l'Environnement et Moléculaire Structurale, CHEMS, Université Constantine 1, 25000 , Algeria.
authors.forename: Hayet
authors.initials: H
authors.lastname: Anana
authors.affiliation: Unité de Recherche de Chimie de l'Environnement et Moléculaire Structurale, CHEMS, Université Constantine 1, 25000 , Algeria.
authors.forename: Chahrazed
authors.initials: C
authors.lastname: Trifa
authors.affiliation: Département Sciences de la Matière, Faculté des Sciences Exactes et Sciences de la Nature et de la Vie, Université Larbi Ben M'hidi, Oum El Bouaghi, Algeria ; Unité de Recherche de Chimie de l'Environnement et Moléculaire Structurale, CHEMS, Université Constantine 1, 25000 , Algeria.
authors.forename: Sofiane
authors.initials: S
authors.lastname: Bouacida
authors.affiliation: Unité de Recherche de Chimie de l'Environnement et Moléculaire Structurale, CHEMS, Université Constantine 1, 25000 , Algeria.
authors.forename: Chaouki
authors.initials: C
authors.lastname: Boudaren
authors.affiliation: Unité de Recherche de Chimie de l'Environnement et Moléculaire Structurale, CHEMS, Université Constantine 1, 25000 , Algeria.
authors.forename: Hocine
authors.initials: H
authors.lastname: Merazig
keywords: crystal structure; fumaric acid; hydro­thermal synthesis; lanthanum(III) coordination polymer