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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.
21

Charge Transport in Coordination Polymer and Metal-Organic Framework Glasses / 配位高分子および金属-有機構造体ガラスにおける電荷移動に関する研究

MA, NATTAPOL 23 March 2023 (has links)
京都大学 / 新制・課程博士 / 博士(工学) / 甲第24587号 / 工博第5093号 / 新制||工||1975(附属図書館) / 京都大学大学院工学研究科合成・生物化学専攻 / (主査)教授 古川 修平, 教授 生越 友樹, 准教授 堀毛 悟史, 教授 松田 建児 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
22

Copper-Azides : Syntheses, Structures and Magnetic Behavior

Mistry, Subhradeep January 2017 (has links) (PDF)
Extensive research work was carried out in past few decades to synthesize new compounds with extended structures by employing various organic linkers and metals. A large number of potential applications of these coordination polymer materials were explored as it contains both inorganic metals as well as organic molecules. The large open pores of coordination polymer compounds were explored for applications such as absorption, separation, and catalysis etc. whereas the framework part provides a model system to study physical properties such as magnetism, luminescence, ferroelectricity etc. We were mainly interested in designing new magnetic materials with extended structures which is the primary objective of this thesis. To study this a systematic investigations are carried out with azide bridged copper(II) compounds. Azide is a versatile ligand which possesses a large number of bridging modes. On the other hand, the coordination flexibility offered by the copper centres makes it to possess diverse coordination number (4-6) as well as geometry. Copper-azide compounds were synthesized at room temperature and the structure was determined using single-crystal X-ray diffraction studies. Structure and magnetic behavior of the copper-azide compounds were studied and discussed here in this thesis. Further, we have studied selective absorption and separation of aliphatic nitrile compounds by employing a two-dimensional interdigitated coordination polymer. In addition, transformation studies of a Ni5 cluster to a Ni9 cluster have also been carried out. Chapter 1 of this thesis presents a brief overview of azide based compounds and summarizes important copper-azide compounds and their magnetic behavior. In chapter 2, synthesis, structure, and magnetic behavior of two-dimensional copper-azide based compounds have been presented. Field dependent magnetic studies were also carried out for all the compounds. Chapter 3 presents the synthesis, structure, and magnetic behavior of copper-azide compounds where 1,2-diaminopropane was employed as a site blocking agent. In chapter 4, the synthesis, structure, and magnetic behavior of two isostructural three-dimensional copper-azides are presented. In chapter 5, synthesis, structure, and magnetic behavior of the azide based one and two-dimensional compounds are presented. Chapter 6 presents synthesis and structure of a two-dimensional inter-digitated coordination polymer compounds. The selective absorption and separation of aliphatic nitriles were also presented in this chapter. In chapter 7, synthesis, structure, and magnetic behavior of Ni clusters are presented. A transformation study to convert a Ni5 cluster to Ni9 cluster was also carried out and presented in this chapter.
23

Pendant Functional Groups in Metal-Organic Frameworks - Effects on Crystal Structure, Stability, and Gas Sorption Properties

Makal, Trevor Arnold 03 October 2013 (has links)
The primary goal of this research concerns the synthesis and characterization of metal-organic frameworks (MOFs) grafted with pendant alkyl substituents to enhance stability and gas sorption properties for use in clean-energy related technologies. Initially, the focus of this work was on the synthesis and comparison of two isostructural MOFs built upon octahedral secondary building blocks; one with no alkyl substituents, and its dimethyl-substituted counterpart. The dimethyl-substituents are observed to enhance the stability of the framework, resulting in high Langmuir surface area (4859 m2 g-1) and hydrogen uptake capacity at 77 K and 1 bar (2.6 wt%). In the second section, the length of pendant alkoxy substituents in semi-flexible MOFs was evaluated through the synthesis and characterization of two isostructural MOFs, one with dimethoxy (PCN-38) and one with diethoxy pendant groups (PCN-39). While PCN-38 exhibited moderate surface area and hydrogen uptake capacities, PCN-39 underwent structural change upon activation leading to a redistribution of pore sizes and selective adsorption of hydrogen over larger gases. This structural transformation is believed to originate from optimal space filling of the pendant groups. In the third section, a series of NbO-type MOFs were synthesized with dimethoxy, diethoxy, dipropoxy, and dihexyloxy substituents and the relationship between chain length and framework stability identified. Increasing chain length was observed to increase moisture stability of the MOFs, resulting in a superhydrophobic material in the case of the dihexyloxy derivative. Thermal stability, however, decreased with increasing chain length, as evidenced from in situ synchrotron powder X-ray diffraction measurements (PXRD). This is in contrast to data obtained from thermogravimetric analysis and shows that the standard use of thermogravimetric analysis, which measures combustion temperatures, may not always provide an accurate description of the thermal stability of MOFs. The role of pendant groups in gas adsorption processes was evaluated through identification of side chains and guest species in the pores of MOFs through in situ synchrotron PXRD measurements. In summary, three separate isostructural series of MOFs with various pendant groups have been discussed in this dissertation, with the roles of those pendant groups toward crystal structure, stability, and gas sorption properties analyzed.
24

Síntese e análise estrutural de polímeros de coordenação e compostos moleculares derivados de Hg(TeAr)2. / Synthesis and structural analysis of coordination polymers and molecular compounds derived from Hg(TeAr)2.

Reckziegel, Poliana 27 July 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work presents a study related to the synthesis and structural analysis of coordination polymers and molecular compounds derived from Hg(TeAr)2. Was used as starting reagents some Hg(TeAr)2, considered basic building blocks for synthesis inorganic, and dithioligands of the type carbamate and phosphate, since they are extremely versatile in complexation to transition elements. The compounds obtained were: [Hg(TePh)(S2CNEt2)]n (1), [Hg(TePh){S2P(OEt)2}]n (2), [Hg(TePh)(S2CNC4H8)]n (3), [Hg2(Tedmb)2(S2CNC4H8)2]n (4), [Hg(dmb)(S2CNC4H8)] (5), [Hg(Temes)(S2CNC4H8)]n (6) e [Hg(mes)(S2CNC4H8)] (7), being can perform a structural study all these compounds, using as the main tool method the X-ray diffraction in sigle crystal, in addition to infrared spectroscopy and elementar analysis. Based on the structural analysis of these compounds can be concluded that the organization of crystal packing and the formation of supramolecular structures depends largely on the choice of appropriate ligands, being can thus control over the coupling between the minimum units generated, making possible to obtain systems really polymeric or molecular. / Este trabalho apresenta o estudo relacionado à síntese e a caracterização estrutural de novos polímeros de coordenação e compostos moleculares derivados de Hg(TeAr)2. Utilizou-se como reagentes de partida alguns Hg(TeAr)2, considerados blocos de montagem básicos para síntese inorgânica, e ditioligantes do tipo carbamato e fosfato, uma vez que estes são de extrema versatilidade na complexação a elementos de transição. Os compostos obtidos foram: [Hg(TePh)(S2CNEt2)]n (1), [Hg(TePh){S2P(OEt)2}]n (2), [Hg(TePh)(S2CNC4H8)]n (3), [Hg2(Tedmb)2(S2CNC4H8)2]n (4), [Hg(dmb)(S2CNC4H8)] (5), [Hg(Temes)(S2CNC4H8)]n (6) e [Hg(mes)(S2CNC4H8)] (7), sendo possível efetuar um estudo estrutural de todos esses compostos, utilizando como ferramenta principal o método de difração de raios X em monocristal, além da espectroscopia de infravermelho e análise elementar. A partir da análise estrutural desses compostos pode-se concluir que a organização do empacotamento cristalino e a formação de estruturas supramoleculares depende imensamente da escolha de ligantes adequados, sendo possível desta forma um controle sobre o acoplamento entre as unidades mínimas geradas, possibilitando a obtenção de sistemas realmente poliméricos ou moleculares.
25

Transfert d'électron photoinduit au sein d'assemblages hétérométalliques associant le [Ru(bpy)3]2+ à des complexes bisterpyridine du Fe(II), Co(III) et Cr(III) / Photoinduced electron transfer within heterometallic assemblies of [Ru(bpy)3]2+ linked to bisterpyridine complexes of Fe(II), Co(III) and Cr(III)

Farran, Rajaa 11 September 2015 (has links)
La thèse commence le 1er octobre 2012. IL s'agit pour cette première année de thèse de synthétiser différents complexes de coordination a base du Ruthénium, Fer, Manganèse et de Cobalt à ligands polypyridinique. Ces complexes seront ensuite assemblés par lien covalent. Nous proposons d'utiliser entre autre les techniques d'electrochimie pour induire ces couplages. On cherchera aussi a immobiliser les assemblages sur surface. La principale difficulté attendue dans cette etape du travail concerne la fonctionalisation dissymétrique des ligands pour l'obtention de triade. / This thesis deals with the synthesis and characterization of inorganic triads for photoinduced charge separation. A range of photosensitizers will be studied, and the effect of the donor and acceptor will be assesed as well. These systems will be studied in solution and immobalized on surfaces. Cette thèse traite de la synthèse et la caractérisation des triades inorganiques pour la séparation de charge photoinduite. Une gamme de photosensibilisateurs seront étudiées, et l'effet du donneur et accepteur sera ainsi étudié. Ces systèmes seront étudiés en solution et immobalizes sur les surfaces.
26

Formação de redes metalo-orgânicas porosas a partir da combinação de ácidos carboxílicos e metais da 1ª série de transição

Scaldini, Felipe Mageste 25 February 2013 (has links)
Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-05-22T15:47:02Z No. of bitstreams: 1 felipemagestescaldini.pdf: 2661212 bytes, checksum: 68339e788685f873502440bba4b26794 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-05-22T17:40:25Z (GMT) No. of bitstreams: 1 felipemagestescaldini.pdf: 2661212 bytes, checksum: 68339e788685f873502440bba4b26794 (MD5) / Made available in DSpace on 2017-05-22T17:40:25Z (GMT). No. of bitstreams: 1 felipemagestescaldini.pdf: 2661212 bytes, checksum: 68339e788685f873502440bba4b26794 (MD5) Previous issue date: 2013-02-25 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Este trabalho descreve a síntese e caracterização de oito compostos de coordenação, [Zn(PYA)2(H2O)2]n (1), [Mn(PYA)2(H2O)2]n (2), {[Co(2,5PDC)(H2O)2] .H2O}n (3), [Mn(2,5HPDC)2(H2O)2] (4), [Ni(2,3HPDC)2(H2O)2] (5), {[Cu(3,4HPDC)2(H2O)2] .DMSO}n (6), {[Co(3,4HPDC)2(H2O)2](H2O)(DMSO)}n (7) e {[Cu2(3,4HPDC)2(H2O)5]}n (8) contendo ligantes da família dos ácidos piridinodicarboxílicos, que são N-, O- doadores e podem proporcionar modos de coordenação interessantes frente aos íons metálicos da 1º série de transição selecionados para o trabalho (Mn2+, Co2+, Ni2+, Cu2+ e Zn2+). Os ligantes utilizados foram os ácidos 2,3 piridinodicarboxílico (2,3H2PDC), 2,5 piridinodicarboxílico (2,5H2PDC), 3,4 piridinodicarboxílico (3,4H2PDC), trans-3-(piridil)-acrílico (HPYA) e 3-(2-tienil)acrílico (HTA). Dos oito compostos descritos neste trabalho, apenas três são inéditos. Os compostos inéditos, (6), (7) e (8) foram caracterizados por análise elementar, análise térmica (TG e DTA), espectroscopia vibracional na região do infravermelho, e difração de raios X por monocristal. Nesses três compostos, em acordo com os dados espectroscópicos, a difração de raios X por monocristal mostrou que os ligantes se apresentam na forma parcialmente desprotonada e além disso, observou-se a formação de redes poliméricas. Em todos os casos, os arranjos supramoleculares são formados por ligações de hidrogênio. Todos os compostos apresentam o metal central em geometria octaédrica, com excessão do composto (8) que mostra dois centros de Cu(II), sendo um em geometria octaédrica e outro como pirâmide de base quadrada. Foi feita também a descrição topológica das redes poliméricas formadas, com auxilio do programa TOPOS. Dentre os compostos apresentados neste trabalho, apenas os compostos (4) e (5) não formam cadeias ou redes poliméricas. O teste de capacidade de adsorção de gás para o composto polimérico (6) foi feito através das isotermas de N2, utilizando o método BET. / This work describes the synthesis and characterization of eight coordination compounds, [Zn(PYA)2(H2O)2]n (1), [Mn(PYA)2(H2O)2]n (2), {[Co(2,5PDC)(H2O)2] .H2O}n (3), [Mn(2,5HPDC)2(H2O)2] (4), [Ni(2,3HPDC)2(H2O)2] (5), {[Cu(3,4HPDC)2(H2O)2] .DMSO}n (6), {[Co(3,4HPDC)2(H2O)2](H2O)(DMSO)}n (7) and {[Cu2(3,4HPDC)2(H2O)5]}n (8) containing N-,O-donor ligands from pyridinedicarboxylic acids family that can provide interesting coordination modes toward the first row transition metal ions (Mn2+, Co2+, Ni2+, Cu2+ e Zn2+). 2,3 pyridinedicarboxylic (2,3H2PDC), 2,5 pyridinedicarboxylic (2,5H2PDC), 3,4 pyridinedicarboxylic (3,4H2PDC), trans-3-(pyridyl)-acrylic (HPYA) and 3-(2-thienyl)acrylic acid (HTA) were used as ligands. Among the eight compounds described in this work, only three are unpublished. The novel compounds, (6), (7) and (8) were characterized by elemental analysis, thermal analysis (TG and DTA), infrared vibrational spectroscopy, and single crystal X-ray diffraction analysis. In these three compounds, in accordance with the spectroscopic data, single crystal X-ray diffraction analysis showed that the ligands are present in partially deprotonated form and furthermore, the formation of polymeric networks was observed. In all cases, supramolecular arrangements are formed by hydrogen bonds. All compounds show the metal center in octahedral geometry, except compound (8) that has two Cu (II) centers; one in octahedral geometry and other in a square pyramidal geometry. A topological description was also made for the polymeric networks formed, supported by the software TOPOS. Among all compounds presented in this work, only compounds (4) and (5) do not form polymeric chains or networks. The gas adsorption capacity test was realized for the polymeric compound (6), through N2 isothermal, using BET method.
27

Conception et propriétés photophysiques de polymères de coordination et de polymères organométalliques / Conception and photophysical properties of coordination and organometallic polymers

Lapprand, Antony 10 April 2015 (has links)
Ces travaux portent sur la conception et l’étude des propriétés photophysiques de polymères de coordination et organométalliques. Dans un premier temps, nous nous sommes intéressés aux adduits formés à partir d’halogénure de cuivre(I) (CuxXyLz ; X= I, Br, Cl). Cette famille de composés possède une grande richesse structurelle de part les conditions de synthèse (choix du ligand, stoechiométrie, choix du solvant, température…) et des propriétés de luminescence variées. Nous nous sommes concentrés sur la synthèse, la caractérisation physique et photophysique d’adduits de CuX à ligands de types monothioéther (RSR) et dithioéther (RS(CH2)nSR). Nous avons ensuite étendu notre étude aux adduits CuX coordinés à des ligands P-chirogéniques (i.e chiralité portée par l’atome de phosphore) puis à des adduits CuX coordinés à la fois par des ligands phosphorés (PPh3 ou dppm) et par des ligands mono- ou dithioéthers. Dans un second temps, nous avons voulu connaître l’impact de l’incorporation de ligands P-chirogéniques (P(C17H35)(Ph)(i-Pr)) sur les propriétés photophysiques de polymères organométalliques conjugués 1D à base de platine(II) et de ligands arylbiséthynyles (-C≡C(Ar)C≡C-). Ce type de polymère basé sur le platine(II) est souvent utilisé comme modèle dans la compréhension des transferts d’énergie dans les états excités. Ces polymères, une fois caractérisés, ont été comparés aux analogues achiraux contenant le fragment trans-Pt(P(PBu)3)2 et plusieurs différences ont été notées. Les observations et conclusions sur la relation structure-propriété sont utiles pour la conception future de matériaux photoniques portant des groupements chiraux. / This work focuses on the design and study of photophysical properties of coordination and organometallics polymers. Initially, we focused on adducts formed from copper(I) halides (CuxXyLz; X = I, Br, Cl). Indeed, these compounds have great structural diversity depending on the synthesis conditions (nature of ligand, stoichiometry, choice of solvent, temperature...) and various luminescence properties. We focused on the synthesis, physical and photophysical characterization of copper(I) halide adducts based on monothioether (RSR) and dithioether (RS(CH2)nSR) ligands. Then, we extended our study to the adducts of copper(I) halide coordinated by phosphorus P-chirogenics ligands (ie chirality carried by the phosphorus atom) and then to CuX adducts coordinated by both phosphorus ligands (PPh3 or dppm)) and mono- or dithioether ligands. Secondly, the impact of the incorporation of P-chirogenics ligands (P(C17H35)(Ph)(i-Pr)) on the photophysical properties of organometallic conjugated polymers 1D based on platinum(II) and arylbisethynyles ligands (-C≡C(Ar)C≡C-) was investigated. This type of polymer based on platinum(II) is often used as a model for the understanding of excited states energy transfers. These polymers, once characterized, were compared to the achiral analogues containing the fragment of trans-Pt(P(PBu)3)2 and several differences were noted. The findings and conclusions on the structure-property relationship are useful in the future design of photonic materials bearing chiral groups.
28

Microscopie par génération de somme de fréquences optiques : application aux polymères de coordination chiraux / Optical sum-frequency generation microscopy : application to chiral coordination polymers

Taupier, Gregory 29 November 2016 (has links)
Nous avons mis en place un dispositif de microscopie par génération de somme de fréquences optiques pour étudier les milieux isotropes chiraux. Ce dispositif a tout d'abord été validé en utilisant la molécule chirale de bi-2-naphtol en solution liquide et en milieu sol-gel. Nous avons établi les conditions expérimentales permettant de limiter les phénomènes de blanchiment par absorption biphotonique du chromophore. Nous avons ensuite entrepris une étude des polymères de coordination chiraux élaborés à partir de l'auto-assemblage de ligands organiques chiraux et d'ions métalliques en solution. Nous avons mesuré un signal SFG chiral apparaissant lors du séchage de films de polymères et de complexes de coordination chiraux. Nous démontrons ainsi que la technique de microscopie SFG spécifique des milieux isotropes chiraux permet de détecter le processus de coordination des polymères de coordination chiraux en phase condensée et de suivre l'établissement de la phase solide. / We have built a set-up to perform sum frequency generation (SFG) microscopy in order to study isotropic chiral media. This set-up was first validated with molecules of bi-2-naphthol in liquid solution and sol-gel matrices. We have established the experimental conditions to limit the bleaching phenomena of the chromophore by two-photon absorption. Next, we have conducted a study of chiral coordination polymers produced through the self-assembly of chiral organic ligands and metal ions in solutions. We have measured a chiral SFG signal developing while films of chiral coordination polymers and complexes are drying. Thus we show that SFG microscopy specific to isotropic chiral media makes it possible to detect the coordination process of chiral coordination polymers in the condensed phase and monitor the establishment of the solid phase.
29

Study on Novel Proton Conducting Behavior in Free-Standing Coordination Polymer Membranes / 自立型配位高分子膜における特異なプロトン伝導挙動に関する研究

Lu, Jiangfeng 25 September 2023 (has links)
京都大学 / 新制・課程博士 / 博士(理学) / 甲第24873号 / 理博第4983号 / 新制||理||1711(附属図書館) / 京都大学大学院理学研究科化学専攻 / (主査)教授 北川 宏, 教授 有賀 哲也, 教授 堀毛 悟史 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
30

Optoelectronically Active Metal-Inorganic Frameworks and Supramolecular Extended Solids

Ivy, Joshua F. 08 1900 (has links)
Metal-organic frameworks (MOFs) have been intensely researched over the past 20 years. In this dissertation, metal-inorganic frameworks (MIFs), a new class of porous and nonporous materials using inorganic complexes as linkers, in lieu of traditional organic linkers in MOFs is reported. Besides novel MIF regimes, the previously described fluorous MOF "FMOF-1", is re-categorized herein as "F-MIF1". F-MIF-1 is comprised of [Ag4Tz6]2- (Tz = 3,5-bis-trifluoromethyl-1,2,4-triazolate) inorganic clusters connected by 3-coordinate Ag+ metal centers. Chapter 2 describes isosteric heat of adsorption studies of F-MIF1 for CO2 at near ambient temperatures, suggesting promise for carbon capture and storage. We then successfully exchanged some of these Ag(I) centers with Au(I) to form an isostructural Au/F-MIF1. Other, nonporous MIFs have been synthesized using Ag2Tz2 clusters with bridging diamine linkers 4,4'-bipyridine, pyrazine, and a Pt(II) complex containing two oppositely-situated non-coordinating pyridines. This strategy attained luminescent products better-positioned for photonic devices than porous materials due to greater exciton density. Chapter 3 overviews work using an entirely inorganic luminescent complex, [Pt2(P2O5)4]4- (a.k.a. "PtPOP") to form new carbon-free MIFs. PtPOP is highly luminescent in solution, but as a solid shows poor quantum yield (QY ~0.02) and poor stability under ambient conditions. By complexing PtPOP to various metals, we have shown a dramatic enhancement in its solid-state luminescence (by an order of magnitude) and stability (from day to year scale). One embodiment (MIF-1) demonstrates microporous character. Chapter 4 overviews the design and application of new MIF linkers. Pt complexes based upon (pyridyl)azolates, functionalized with carboxylic acid groups, have been synthesized. These complexes, and their esterized precursors, show strong luminescence on their own. They have been used to generate new luminescent MIFs. Such new MIFs may be useful toward future inorganic (LEDs) or organic (OLEDs) light-emitting diodes, respectively. The electronic communication along their infinite coordination structures is desirable for color tuning and enhanced conductivity functions, compared to the small molecules used in such technologies, which rely on intermolecular interactions for these functions.

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