Photochromism of a 3D CdII Complex with Two Captured Ligand Isomers Generated In Situ from the Same Precursor

Data on the synthesis and physicochemical studies of salts of mono- or dibasic unsaturated carboxylic acids and unsaturated metal oxo-carboxylates are generalised and described systematically. The structures and properties of the COO group in various compounds and characteristic features of the structures of carboxylate complexes are analysed. The main routes and kinetics of polymerisation transformations of unsaturated metal carboxylates are considered. The attention is focused on the effect of the metal ion on the monomer reactivity and the polymer morphology and structure. The possibility of stereochemical control of radical polymerisation of unsaturated metal carboxylates is demonstrated. The electronic, magnetic, optical, absorption and thermal properties of metal (co)polymers and nanocomposites and their main applications are considered.

https://iopscience.iop.org/article/10.1070/RC2008v077n03ABEH003682/pdf

Macromolecular metal carboxylates

Biofilm formation and its effects on microbiologically influenced corrosion of carbon steel in oilfield injection water via electrochemical techniques and scanning electron microscopy.

The structures of three new polymeric lanthanide complexes, poly[[bis(2,2'-bipyridine)-mu(4)-itaconato-di-mu(3)-itaconato-digadolinium(III)] tetrahydrate], {[Gd(2)(C(5)H(4)O(4))(3)(C(10)H(8)N(2))(2)].4H(2)O}(n), (I), poly[diaqua(2,2'-bipyridine)di-mu(3)-itaconato-mu(2)-itaconato-digadolinium(III)], [Gd(2)(C(5)H(4)O(4))(3)(C(10)H(8)N(2))(H(2)O)(2)](n), (II), and poly[[bis(2,2'-bipyridine)-mu(4)-itaconato-di-mu(3)-itaconato-diholmium(III)] dihydrate], {[Ho(2)(C(5)H(4)O(4))(3)(C(10)H(8)N(2))(2)].2H(2)O}(n), (III), have been solved from twinned specimens. Compound (I) presents a two-dimensional polymeric structure parallel to (011) built up around two independent nine-coordinated Gd centres displaying similar GdO(7)N(2) environments, with both N-donor atoms in each provided by a chelating 2,2'-bipyridine (bpy) unit. The coordinating O atoms are from three different itaconate (ita) anions (itaconic acid is 2-methylidenebutanedioic acid). Compound (II) also presents two independent Gd centres (one ten- and the other eight-coordinated), but the overall formula and individual coordinations are different from those of (I). The chemical unit is in this case completed by one bpy ligand, three ita anions (one of them displaying a new, hitherto unreported, mu(3)-O,O':O',O'':O''' binding mode) and two aqua ligands. The whole structure is built up around a twofold rotation axis passing through both cations, as well as through the centre of the bpy ligand and one of the ita anions, thus making only half of the chemical unit independent. Finally, compound (III) presents a single independent Ho centre, a bpy unit and one and a half ita anions (one of them bisected by a twofold rotation axis) in the asymmetric unit, plus two (disordered) nonbonded solvent water molecules. In compounds (II) and (III), those ita anions bisected by a symmetry element incompatible with the internal symmetry of the ligand exhibit disorder in the C=CH(2) group.

/pdf/three-lanthanide-complexes-derived-from-itaconic-acid-and-2-31x6c9m3xd.pdf

Three lanthanide complexes derived from itaconic acid and 2,2'-bipyridine.

Synthesis and X-ray powder diffraction data of transition metal derivatives of maleic acid. I. M[sup 2+](C[sub 4]H[sub 3]O[sub 4][sup -])[sub 2]⋅4H[sub 2]O (M[sup 2+]=Mn, Fe, Co, Ni, and Zn)

[Cd(C5H4O4)(OH2)2] (1), crystallizes in the monoclinic system, space groupP21/n, with lattice parametersa=7.323(2),b=16.028(6),c=7.202(2) A, β=113.11(1)°, andZ=4. The Cd atom coordinates to seven oxygens in a monocapped trigonal antiprism fashion. The antiprisms share one vertex to form chains which run approximately parallel to thec axis. The itaconate ligands link the chains to form layers which stack along theb axis.

Structure of diaqua(itaconato) cadmium(II), [Cd(C5H4O4)(OH2)2]

Este trabajo presenta la evaluacion de los productos de corrosion de sulfuro de hierro generados sobre acero al carbono por la accion corrosiva de una cepa pura de Bacterias Sulfato-Reductoras (SRB), la Desulfovibrio desulfuricans desulfuricans, a diferentes tiempos de exposicion, y su correlacion con el contaje planctonico y sesil, la perdida de peso y la morfologia de ataque Los resultados usando Difraccion de Rayos-X (XRD) indicaron que el sulfuro de hierro identificado como Mackinawita predomina sobre otros compuestos de sulfuro de hierro; lo cual fue confirmado usando Espectroscopia Fotoelectronica de Rayos-X (XPS); ya que los monosulfuros predominaron sobre los disulfuros La correlacion entre todas las variables medidas permitio demostrar que la Mackinawita formada bioticamente no protege al acero; debido a que la corrosion localizada generada por este tipo de bacterias se incremento con el tiempo de exposicion

J. Contreras

Papers

Structure of diaqua(itaconato) cadmium(II), [Cd(C5H4O4)(OH2)2]

Evaluación de productos de corrosión de sulfuros de hierro generados por Bacterias Sulfato-Reductoras