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Title: Structure and decomposition of the silver formate Ag(HCO{sub 2})

Abstract

Crystal structure of the silver formate Ag(HCO{sub 2}) has been determined (orthorhombic, sp.gr. Pccn, a=7.1199(5), b=10.3737(4), c=6.4701(3)Å, V=477.88(4) Å{sup 3}, Z=8). The structure contains isolated formate ions and the pairs Ag{sub 2}{sup 2+} which form the layers in (001) planes (the shortest Ag–Ag distances is 2.919 in the pair and 3.421 and 3.716 Å between the nearest Ag atoms of adjacent pairs). Silver formate is unstable compound which decompose spontaneously vs time. Decomposition was studied using Rietveld analysis of the powder diffraction patterns. It was concluded that the diffusion of Ag atoms leads to the formation of plate-like metal particles as nuclei in the (100) planes which settle parallel to (001) planes of the silver formate matrix. - Highlights: • Silver formate Ag(HCO{sub 2}) was synthesized and characterized. • Layered packing of Ag-Ag pairs in the structure was found. • Decomposition of Ag(HCO{sub 2}) and formation of metal phase were studied. • Rietveld-refined micro-structural characteristics during decomposition reveal the space relationship between the matrix structure and forming Ag phase REPLACE with: Space relationship between the matrix structure and forming Ag phase.

Authors:
; ;
Publication Date:
OSTI Identifier:
22658192
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 246; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ACID CARBONATES; CRYSTAL STRUCTURE; DECOMPOSITION; FORMATES; ORTHORHOMBIC LATTICES; SILVER IONS

Citation Formats

Puzan, Anna N., E-mail: anna_puzan@mail.ru, Baumer, Vyacheslav N., and Mateychenko, Pavel V.. Structure and decomposition of the silver formate Ag(HCO{sub 2}). United States: N. p., 2017. Web. doi:10.1016/J.JSSC.2016.11.022.
Puzan, Anna N., E-mail: anna_puzan@mail.ru, Baumer, Vyacheslav N., & Mateychenko, Pavel V.. Structure and decomposition of the silver formate Ag(HCO{sub 2}). United States. doi:10.1016/J.JSSC.2016.11.022.
Puzan, Anna N., E-mail: anna_puzan@mail.ru, Baumer, Vyacheslav N., and Mateychenko, Pavel V.. Wed . "Structure and decomposition of the silver formate Ag(HCO{sub 2})". United States. doi:10.1016/J.JSSC.2016.11.022.
@article{osti_22658192,
title = {Structure and decomposition of the silver formate Ag(HCO{sub 2})},
author = {Puzan, Anna N., E-mail: anna_puzan@mail.ru and Baumer, Vyacheslav N. and Mateychenko, Pavel V.},
abstractNote = {Crystal structure of the silver formate Ag(HCO{sub 2}) has been determined (orthorhombic, sp.gr. Pccn, a=7.1199(5), b=10.3737(4), c=6.4701(3)Å, V=477.88(4) Å{sup 3}, Z=8). The structure contains isolated formate ions and the pairs Ag{sub 2}{sup 2+} which form the layers in (001) planes (the shortest Ag–Ag distances is 2.919 in the pair and 3.421 and 3.716 Å between the nearest Ag atoms of adjacent pairs). Silver formate is unstable compound which decompose spontaneously vs time. Decomposition was studied using Rietveld analysis of the powder diffraction patterns. It was concluded that the diffusion of Ag atoms leads to the formation of plate-like metal particles as nuclei in the (100) planes which settle parallel to (001) planes of the silver formate matrix. - Highlights: • Silver formate Ag(HCO{sub 2}) was synthesized and characterized. • Layered packing of Ag-Ag pairs in the structure was found. • Decomposition of Ag(HCO{sub 2}) and formation of metal phase were studied. • Rietveld-refined micro-structural characteristics during decomposition reveal the space relationship between the matrix structure and forming Ag phase REPLACE with: Space relationship between the matrix structure and forming Ag phase.},
doi = {10.1016/J.JSSC.2016.11.022},
journal = {Journal of Solid State Chemistry},
number = ,
volume = 246,
place = {United States},
year = {Wed Feb 15 00:00:00 EST 2017},
month = {Wed Feb 15 00:00:00 EST 2017}
}
  • Two new families of lanthanide complexes associating the ligand oxalate and carbonate or oxalate and formate have been prepared under autogenous pressure at 200{degrees}C using a pseudo-hydrothermal method. The two families have been extended to some lanthanides (Ln): oxalate-carbonate Ln = Ce, Pr, Nd, and Eu; oxalate-formate Ln = La, Ce, and Sm. The starting suspension contains either oxalate or a mixture of oxalate and oxalic acid. The structures have been solved for the element cerium. In both cases, the structure is built up form cerium atoms sharing all their oxygen atoms with oxalate and carbonate or oxalate and formatemore » ligands thus forming a three-dimensional network. The cerium polyhedra share either faces or edges or corners. The coordination scheme of the oxalate ligands is variable: bischelating, bischelating and monodentate, or bischelating and bismonodentate. The carbonate group acts as a bischelating and bismonodentate ligand while the formate group is chelating and monodentate. The characterization of these two original families by infrared spectra and thermal behavior is presented for some pure phases. A tentative explanation of the synthesis of these two phases will be emphasized.« less
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  • Immobilization of Pd onto TiO{sub 2} powders and colloids results in active photocatalysts for the selective reduction of CO{sub 2}/HCO{sub 3}{sup {minus}} to formate. The photocatalytic reduction of CO{sub 2}/HCO{sub 3}{sup {minus}} to HCO{sub 2}{sup {minus}} is inhibited by mercaptoethanol. Concomitant with the decline in formate production, the rate of H{sub 2} production increases. The inhibition of CO{sub 2}/HCO{sub 3}{sup {minus}} reduction is attributed to the binding of mercaptoethanol to the HCO{sub 3}{sup {minus}}-activation sites of Pd. A mechanism is invoked in which the photogenerated conduction-band electrons of TiO{sub 2} either directly reduce protons to H{sub 2} on the semiconductormore » surface or else reduce protons on the Pd surface to produce palladium hydride. The latter species reduces the Pd-activated HCO{sub 3}{sup {minus}} to formate.« less
  • The synthesis and X-ray diffraction study of compound ([Ag{sub 2}Ge(HCit){sub 2}(H{sub 2}O){sub 2}] ∙ 2H{sub 2}O){sub n}, where H{sub 4}Cit is the citric acid, are performed. In the polymeric structure, the HCit{sup 3–} ligand fulfils the tetradentate chelate–μ{sub 4}-bridging (3Ag, Ge) function (tridentate with respect to Ge and Ag atoms). The Ge atom is octahedrally coordinated by six O atoms of two HCit{sup 3–}ligands. The coordination polyhedron of the Ag atom is an irregular five-vertex polyhedron [four O atoms of four HCit{sup 3–} ligands and the O(H{sub 2}O) atom]. An extended system of O–H···O hydrogen bonds connects complex molecules intomore » a supramolecular 3D-framework.« less
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