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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Synthesis of new [1111]metacyclophane ligands for the formation of molecular coordination networks / Synthèse de nouveaux ligands à base de [1111] metacyclophane pour la formation de réseaux de coordination moléculaires

Chernova, Ekaterina 17 October 2018 (has links)
En termes de chimie supramoléculaire et de tectonique moléculaire, les métacyclophanes [1111] sont des composés attractifs pour la préparation et l’étude de réseaux moléculaires, car la particularité de ces composés est la stabilité exceptionnelle de la conformation l'encombrement stérique entre les groupes ortométhyliques des cycles aryles. Un tel type rigide d'échafaudage moléculaire aussi bien avec la présence de sites de liaison de terminaux est considéré comme un bloc de construction moléculaire très approprié pour la formation de différents types de réseaux moléculaires en utilisant principalement la coordination et la H-bonding. Dans le cadre de ce travail, nous avons étudié le rôle de la nature de la coordination des sites greffés sur le squelette métacyclophane macrocyclique afin d'améliorer leur capacité à former des réseaux de coordination dans la phase cristalline et les systèmes supramoléculaires en solution, une série de nouvelles [1111] métacyclophanes ont été synthétisés et caractérisés en solution et à l'état solide. Leur propension à lier différents cations métalliques dans la phase cristalline ainsi que des complexes en solution ont été étudiés. / In terms of supramolecular chemistry and molecular tectonics,[1111]metacyclophanes are attractive compounds for the preparation and study of molecular networks since the particular feature of these compounds is determined by exceptional stability of the 1,3-Alternate conformation of their molecular platform due to the steric hindrance between the orto-methyl groups of aryl rings. Such rigid type of molecular scaffold both with presence of terminal binding sites is considered as a very suitable molecular building block for formation of different type molecular networks using primarily coordination and H-bonding. Through this work we investigated the role of the nature of the coordinating sites grafted on the metacyclophane macrocyclic backbone in order to enhance their ability to form coordination networks in the crystalline phase and the supramolecular systems in solution, a series of new [1111]metacyclophanes have been synthesized and characterized in solution and in the solid state. Their propensity to bind different metal cations in the crystalline phase as well as complexes in solution have been studied.
2

Estudo te?rico QTAIM e DFT dos compostos de coordena??o: efeito quelato, titanocenos e liga??o qu?mica

Santos, Hugo Felix Lima dos 15 October 2012 (has links)
Made available in DSpace on 2014-12-17T15:42:03Z (GMT). No. of bitstreams: 1 HugoFLS_DISSERT.pdf: 2820205 bytes, checksum: ad87619352b0e479d50e7f9093be5ec0 (MD5) Previous issue date: 2012-10-15 / This work is a study of coordination compounds by quantum theory of atoms in molecules (QTAIM), based on the topological analysis of the electron density of molecular systems, both theoretically and experimentally obtained. The coordination chemistry topics which were studied are the chelate effect, bent titanocene and chemical bond in coordination complexes. The chelate effect was investigated according to topological and thermodynamic parameters. The exchange of monodentate ligands on polydentate ligands from same transition metal increases the stability of the complex both from entropy and enthalpy contributions. In some cases, the latter had a higher contribution to the stability of the complex in comparison with entropy. This enthalpic contribution is explained according to topological analysis of the M-ligand bonds where polidentate complex had higher values of electron density of bond critical point, Laplacian of electron density of bond critical point and delocalization index (number of shared electrons between two atoms). In the second chapter, was studied bent titanocenes with bulky cyclopentadienyl derivative π-ligand. The topological study showed the presence of secondary interactions between the atoms of π-ligands or between atoms of π-ligand and -ligand. It was found that, in the case of titanocenes with small difference in point group symmetry and with bulky ligands, there was an nearly linear relationship between stability and delocalization index involving the ring carbon atoms (Cp) and the titanium. However, the titanocene stability is not only related to the interaction between Ti and C atoms of Cp ring, but secondary interactions also play important role on the stability of voluminous titanocenes. The third chapter deals with the chemical bond in coordination compounds by means of QTAIM. The quantum theory of atoms in molecules so far classifies bonds and chemical interactions in two categories: closed shell interaction (ionic bond, hydrogen bond, van der Waals interaction, etc) and shared interaction (covalent bond). Based on topological parameters such as electron density, Laplacian of electron density, delocalization index, among others, was classified the chemical bond in coordination compounds as an intermediate between closed shell and shared interactions / Esse trabalho consiste no estudo dos compostos de coordena??o pela teoria qu?ntica de ?tomos em mol?culas, do ingl?s, QTAIM, fundamentada na an?lise topol?gica da densidade eletr?nica dos sistemas moleculares obtida tanto teoricamente quanto experimentalmente. Os temas escolhidos para serem estudados s?o o efeito quelato, os metalocenos de tit?nio de estrutura pseudotetra?drica e a liga??o coordenada. No primeiro cap?tulo, foi investigado o efeito quelato de acordo com par?metros termodin?micos e topol?gicos. A troca de ligante monodentado am?nia pelo ligante bidentado 1,2-etanodiamina de mesma natureza qu?mica aumenta a estabilidade do ?on complexo, tanto pela contribui??o da entropia, quanto da entalpia, em alguns casos, esta ?ltima teve maior participa??o para a estabilidade do ?on complexo que a entropia. Em todos os ?ons complexos, a troca de ligante monodentado para bidentado levou ao aumento dos valores eletr?nicos da topologia como densidade eletr?nica, Laplaciano da densidade eletr?nica e ?ndice de deslocaliza??o (n?mero de el?trons compartilhados entre dois ?tomos). No segundo cap?tulo, foram estudados os metalocenos de tit?nio de estrutura pseudotetra?drica com ligantes-π volumosos ciclopentadienila (Cp) e seus derivados. O estudo topol?gico mostrou a presen?a de intera??es secund?rias entre os ?tomos dos ligantes-π ou dos ligantes-σ. Verificou-se que, para os metalocenos de tit?nio com pequena diferen?a de simetria pontual e ligantes volumosos, havia uma rela??o quase-linear entre a estabilidade e o ?ndice de deslocaliza??o envolvendo ?tomos de carbono do anel (Cp) e o tit?nio. Contudo, a estabilidade n?o ? relacionada apenas ?s intera??es entre o ?tomo de tit?nio e o anel ciclopentadienila, mas ?s intera??es secund?rias influenciando na estabilidade dos titanocenos com ligantes volumosos. O terceiro cap?tulo trata da liga??o qu?mica nos compostos de coordena??o por meio da QTAIM. A teoria qu?ntica de ?tomos em mol?culas, at? ent?o, classifica as liga??es e intera??es qu?micas em duas categorias: intera??o de camada fechada (liga??o i?nica, liga??o de hidrog?nio, intera??o de van der Waals, entre outras) e intera??o compartilhada (liga??o covalente). Baseado nos par?metros topol?gicos como densidade eletr?nica, Laplaciano da densidade eletr?nica, entre outros, classificou-se a liga??o coordenada como intermedi?ria entre as intera??es de camada fechada e intera??es compartilhadas
3

Development of Functional Organic Materials with an Intramolecular B-N Coordination Bond as a Key Scaffold / 分子内B-N配位結合を鍵骨格にもつ機能性有機材料の開発

Shimogawa, Hiroyuki 23 March 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第20394号 / 工博第4331号 / 新制||工||1671(附属図書館) / 京都大学大学院工学研究科物質エネルギー化学専攻 / (主査)教授 村田 靖次郎, 教授 辻 康之, 教授 中村 正治 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
4

Cristaux moléculaires : des cristaux coeur-coquille aux réseaux de cristaux / Molecular crystals : from core-shell crystals to networks of crystals

Adolf, Cyril 04 October 2017 (has links)
L’agencement relatif de systèmes cristallins moléculaires, par une méthode d’organisation avancée est une stratégie de premier plan. Le développement de tels systèmes permet la conception de dispositifs innovants dans le domaine des matériaux poreux, magnétiques ou optiques.Les travaux menés dans le cadre de cette étude ont pour objectif l’élaboration d’architectures macroscopiques hiérarchisées concernant l’état cristallin, de type « réseaux de cristaux ». Dans un premier temps, le développement et la caractérisation de réseaux iso-structuraux ont été réalisés. Ces séries, formées par liaisons hydrogènes, servent à l’étude de la croissance cristalline épitaxiale, développée par la suite. À partir de ces résultats, la préparation d’architectures monocristallines de type cristal cœur-coquille ainsi que la soudure cristalline sont entreprises.Enfin, la généralisation de cette mise en forme de l’état cristallin à des systèmes formés par liaisons de coordination est présentée. / The relative disposition of applicative molecular systems by an advanced organization method is a well-defined strategy (core-shell type crystals). It is aimed at developing innovative materials.The presented study deals with the elaboration of a new organization method concerning the crystalline matter to obtain “network of crystals”. This strategy of materials processing occurs at a macroscopic scale and in a hierarchical way.Firstly, series of isostructural crystalline molecular networks have been designed with a molecular tectonics approach. These series, formed by hydrogen bonds, are then used for the study of the epitaxial growth of crystal. The preparation of a single crystalline architecture with a defined sequenced area of different compositions is demonstrated: core-shell crystals and welded crystals.Finally, the developed strategy is applied to coordination networks exhibiting luminescent properties in order to generalize the described process.

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