De´termination pre´cise de la structure de la chiolite Na5Al3F14 ete´tude par R.P.E. de Na5Al3F14:Cr3+

Jacoboni, C.; Leblé, A.; Rousseau, Jean‐Jacques

doi:10.1016/0022-4596(81)90440-0

Cited by 71 publications

(51 citation statements)

References 13 publications

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“…The most complex tellurate layer type has corner-sharing of Q 2400 and Q 4200 octahedra to form a layer with overall stoichiometry Te 3 X 14 ( Fig. 14d), with the same topology as that seen in chiolite, Na 5 (Al 3 F 14 ) (Jacoboni et al, 1981).…”

Section: -362mentioning

confidence: 94%

A review of the structural architecture of tellurium oxycompounds

2016

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Relative to its extremely low abundance in the Earth's crust, tellurium is the most mineralogically diverse chemical element, with over 160 mineral species known that contain essential Te, many of them with unique crystal structures. We review the crystal structures of 703 tellurium oxysalts for which good refinements exist, including 55 that are known to occur as minerals. The dataset is restricted to compounds where oxygen is the only ligand that is strongly bound to Te, but most of the Periodic 4+ cations display one-sided 3-, 4-or 5-coordination by oxygen (with rare examples of coordination numbers 2 and 6). For both valence states of Te, examples are known of Te m O n complexes which are monomeric (m = 1; neso), noncyclic finite oligomers (soro), rings (cyclo), infinite chains (ino), layers ( phyllo) and frameworks (tecto tellurates). There is a clear analogy to the polymerization classes that are known for silicate anions, but the behaviour of Te is much richer than that of Si for several reasons: (1) the existence of two cationic valence states for Te; (2) the occurrence of multiple coordination numbers; (3) the possibility of edge-sharing by TeO n polyhedra; (4) the possibility for oxygen ligands to be 3-coordinated by Te; and (5) the occurrence of Te m O n polymers that are cationic, as well as neutral or anionic. While most compounds contain only one or two symmetrically distinct types of Te atom, Pauling's Fifth Rule is frequently violated, and stoichiometrically simple compounds such as CaTeO 3 can have polymorphs with up to 18 distinct Te sites. There is a tendency for local symmetry features such as the threefold axis of a TeO 6 octahedron or the acentric symmetry of a Te 4+ O n polyhedron to be inherited by the host structure; the latter in particular can lead to useful physical properties such as nonlinear optical behaviour. We develop for the first time a hierarchical taxonomy of Te-oxysalt structures, based upon (1) valence state of Te; (2) polymerization state of Te m O n complexes; (3) polymerization state of larger strongly-bound structural units that include non-Te cations. Structures are readily located and compared within this classification.

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Section: -362mentioning

confidence: 94%

A review of the structural architecture of tellurium oxycompounds

2016

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“…The two independent Na + ions are located at 00½ and, approximately, at ~1 ~" ~;, layers of octahedra are hence separated by cations. Failure to generate second harmonics confirms the centrosymmetric choice of space group at room temperature (Jacoboni et al, 1981). Chiolite is reported to undergo a phase transition at 150K (Rocquet, Couzi, Tressaud, Chaminade & Hauw, 1985).…”

Section: Structural Discussionmentioning

confidence: 83%

“…Both polyhedra are also associated with two additional O,F atoms, at Na--O,F distances greater than 2.8A. In the case of NasAI3F14, one Na is eight-coordinated with a unique Na-F distance of 2.583 A; the second independent Na atom is sixcoordinated with two Na-F distances of 2.268 A, two of 2-290 A and two of 2.583 A (Jacoboni et al, 1981).…”

Section: Structural Discussionmentioning

confidence: 98%

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Coupling of ferroelasticity to ferroelectricity in Na₅W₃O₉F₅ and the structure at 295 K

Abrahams¹,

Marsh

Ravez

1989

Acta Crystallogr Sect B

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“…Os padrões de difração de raios X para as argilas e materiais híbridos, exibidos nas figuras 25 e 26, apresentam perfis semelhantes em todos os casos, sendo estes atribuídos a um difratograma de raios X característico de argilas beidelitas [52], visualizando a presença das reflexões referentes aos planos (001), (hkl) (I) (hkl) [79]. Essa impureza é formada durante a síntese da beidelita em meio contendo fluoreto, e pode ser removida das amostras através de lavagem com água e posterior centrifugação ou filtração.…”

Section: Difratometria De Raios X (Drx)unclassified

Imobilização de complexos oxindolimínicos de cobre e zinco em argilas beidelitas

Couto¹

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2016Ficha Catalográfica Elaborada pela Divisão de Biblioteca e Documentação do Conjunto das Químicas da USP. .345 CDDDedico este trabalho aos amigos próximos e aos que estão longe, e que me apoiaram, incentivaram e não me deixaram desanimar. AGRADECIMENTOSAgradeço primeiramente a Deus pela oportunidade de desenvolver essa Tese.À professora Ana Maria da Costa Ferreira, pela excelente orientação, apoio, compreensão e pelos ensinamentos passados durante o período desta Tese. Sou muito grato pelo incentivo e por acreditar na realização deste trabalho e ter me dado a oportunidade de realizá-lo.À professora Vera Constantino, por aceito a co-orientação deste trabalho e por ter me incentivado a sempre buscar mais e aprender mais.À professora Jocelyne Miehé-Brendlé da Universidade de Haute-Alsace (UHA) emMulhouse na França por ter me recebido em seu laboratório e pela colaboração nos experimentos de preparo das argilas beidelitas, dos materiais híbridos e pelo acesso irrestrito aos equipamentos disponíveis em seu laboratório.Ao professor Lionel Limousy (UHA) pela ajuda nos experimentos de Potencial Zeta e de carga iônica superficial da argila beidelita e seus respectivos materiais híbridos.À técnica de laboratório Laure Michelin (UHA) pelo auxílio nas medidas de difração de raios X e de fluorescência de raios X. with mitochondria leading to a decrease of membrane potential and acting as decoupling agent. Thus, these compounds can induce apoptosis or programmed cell death. Additionally, they inhibit proteins involved in the cell cycle, such as human topoisomerase I and cyclin dependent kinases (CDK1 and CDK2). The beidellites were synthesized and characterized by methods described in the literature.Additionally, in the presence of these complexes were obtained hybrid materials type beidellita/ [complex]. The characterization of clays and the obtained hybrid materials were performed using different techniques: spectroscopy UV/Vis, IR and EPR, thermogravimetric analysis, X-ray powder diffraction. In the characterization of the complexes mass spectrometry (ESI-MS) was also used. The prepared hybrid materials were stable and able to derail tumor cells (HeLa) in the case of hybrid materials with copper(II) compounds, with IC 50 in the range from 0.11 to 0.41 mg/mL.Unlikely, the analogous compounds of zinc(II) and pure clays have proved to be nontoxic facing the same cells. These results indicate a promising possibility of using the beidellites as carriers of these antitumor metal complexes.Keywords: oxindolimine-metal complexes; synthetic beidellites; hybrid materials; spectroscopic characterization; cell viability; antitumor agents. LISTA DE ABREVIATURAS E SIGLASNomenclatura dos ligantes e complexos preparados:epy: 2-(2-aminoetil)piridina isa: isatina INTRODUÇÃO.................................................................................................. ..........................................................................................................32 3. PARTE EXPERIMENTAL....................................

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De´termination pre´cise de la structure de la chiolite Na5Al3F14 ete´tude par R.P.E. de Na5Al3F14:Cr3+

Cited by 71 publications

References 13 publications

A review of the structural architecture of tellurium oxycompounds

A review of the structural architecture of tellurium oxycompounds

Coupling of ferroelasticity to ferroelectricity in Na₅W₃O₉F₅ and the structure at 295 K

Imobilização de complexos oxindolimínicos de cobre e zinco em argilas beidelitas

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De´termination pre´cise de la structure de la chiolite Na5Al3F14 ete´tude par R.P.E. de Na5Al3F14:Cr3+

Cited by 71 publications

References 13 publications

A review of the structural architecture of tellurium oxycompounds

A review of the structural architecture of tellurium oxycompounds

Coupling of ferroelasticity to ferroelectricity in Na5W3O9F5 and the structure at 295 K

Imobilização de complexos oxindolimínicos de cobre e zinco em argilas beidelitas

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Coupling of ferroelasticity to ferroelectricity in Na₅W₃O₉F₅ and the structure at 295 K