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Alkan, Cemil. "Synthesis, Characterization And Electrical Properties Of Diazophenylene And Diazodiphenylene Bridged Co, Ni, Cu, Ce, And Er Phthalocyanine Polymers." Phd thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/2/12605362/index.pdf.
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SYNTHESIS, CHARACTERIZATION, AND ELECTRICAL PROPERTIES OF DIAZOPHENYLENE AND DIAZODIPHENYLENE BRIDGED Co, Ni, Cu, Ce, AND Er PHTHALOCYANINE POLYMERS
Alkan, Cemil
M. Sc., Department of Polymer Science and Technology
Supervisor: Prof.Dr. Leyla Aras
Co- Supervisor: Prof.Dr. Güngö
r Gü
ndü
z September 2004, 112 pages In this research, diazophenylene and diazodiphenylene bridged metal-phthalocyanine polymers were produced from diazonium salt of diaminophenylene/bensidin and pre-synthesized tetraamino metal phthalocyanines. Tetraamino metal phthalocyanine complexes of Co, Ni, Cu, Ce, and Er were obtained by reducing tetranitro metal phthalocyanine complexes synthesized from 3-nitrophthalic anhydride, urea, metal salt, and ammonium molybdate catalyst. Complexes and polymers were characterized by Fourier Transform Infrared Radiation (FTIR) and UV-Visible spectroscopies. X-Ray analysis showed that there were short range orientations in the polymers. Thermal analysis of the complexes and the polymers were done by differential scanning calorimetry and thermal gravimetric analysis at a heating rate of 10&
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Cmin&
#61485
1 under nitrogen atmosphere. Ash analysis was performed to determine the metal content of the polymers. Viscosity and ebullioscopy measurements of the soluble part of the polymers were carried out in THF at 25&
#61616
C. Scanning electron microscopy were used for morphology investigations of the polymers. Four probe conductivity measurements showed that electrical conductivity of the polymers increased according to the metallic conductivity of the metal at the center of the phthalocyanine units. When doped with iodine, the polymer samples showed 104 fold increase in their conductivities. Current-Voltage (I-V) measurements showed that the polymers were optically sensitive and semiconductors. Electrochemical analysis of the soluble part of the polymers were determined in tributylamine perchlorite+dichloromethane mixture utilizing cyclic voltammetry (CV).
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Paredes-Nunez, Anaëlle. "Étude de la réaction d’hydrogénation du CO sur des catalyseurs à base de cobalt supporté par DRIFTS operando." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1200.
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Notre dépendance à l'égard des combustibles fossiles et la diminution des ressources pétrolières nous imposent la recherche de sources renouvelables d'énergie et de produits chimiques. La synthèse Fischer-Tropsch permet de répondre à la demande en carburants propres et renouvelables grâce à l'utilisation de gaz de synthèse issu de la biomasse. L'objectif de ce travail est de contribuer à la compréhension du mécanisme de l'hydrogénation du CO sur des catalyseurs au cobalt et à l'identification du site actif par des études spectroscopiques DRIFTS operando. Ce système permet d'observer les différentes espèces adsorbées à la surface du catalyseur pendant la réaction : CO pontés et linéaires, formiates, carboxylates et hydrocarbures. Nos travaux ont montré qu'une fraction des formiates dits « rapides» peut expliquer la formation du méthanol dans nos conditions de réaction. L'ajout dans le mélange H2+CO d'un élément minéral typique de la biomasse, le chlore sous forme de trichloréthylène, a révélé que, l'activité diminuait. La bande des CO pontés étant la plus impactée et se déplaçant vers les hauts nombres d'onde, l'effet du chlore a été notamment associé à un effet électronique sur le cobalt. L'adsorption du chlore étant réversible, nous avons également étudié l'effet de l'étain. Ce métal n'adsorbe pas le CO dans nos conditions et peut s'adsorber à la surface du cobalt. L'étain empoisonne sélectivement la formation des CO pontés et limite fortement la chimisorption de l'hydrogène. Une relation linéaire entre la vitesse de formation des produits et la proportion de CO pontés est observée, révélant l'importance des CO pontés pour la réaction d'hydrogénation du COOur dependence on fossil fuels and the decrease of oil resources warrant the search for renewable energy sources and chemicals. Fischer-Tropsch synthesis enables meeting the requirements for cleaner and renewable fuels through the use of syngas obtained from biomass.The objective of this work was to contribute to the understanding of the mechanism of CO hydrogenation on cobalt-based catalysts and the identification of the active site by operando DRIFT spectroscopy. Different species were adsorbed on the surface of the catalyst under reaction conditions: bridged and linear CO, formates, carboxylates and hydrocarbons. Our resutls shows that so-called “fast formate” can account for the formation of methanol under our reaction conditions. The study of a typical biomass element, chlorine, revealed that the activity decreased under trichloroethylene,. The CO bridged band being the most affected band and shifting to higher wavenumber, the chlorine effect was partly associated with an electronic effect on cobalt. Chlorine adsorption being reversible, tin poisoning was also studied. This metal does not adsorb CO under our conditions. Tin addition to cobalt selectively poisons bridged CO and greatly limits the chemisorption of hydrogen. A linear relationship between the rate of formation of products and the proportion of CO bridged is observed, highlighting the importance of CO bridged
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Kothe, Thomas. "Reductive Binding of C‒O and Nitro Substrates at a Pyrazolate-Bridged Preorganized Dinickel Scaffold." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://hdl.handle.net/21.11130/00-1735-0000-0005-1524-B.
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Koumousi, Evangelia S. "Synthesis and characterization of dinuclear {Fe(μ-CN)Co} complexes exhibiting metal-to-metal electron transfer properties." Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0306/document.
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Cette thèse porte sur la synthèse de nouveaux complexes binucléaires à ponts cyanures de type {Fe(μ-CN)Co}, qui reproduisent au sein d'une seule molécule les propriétés originales du réseau de coordination d'analogue de bleu de Prusse AxCo[Fe(CN)6]y•nH2O (A=ions alcalins), i.e. un transfert d'électron intramoléculaire thermo- et photo-induit à l'état solide. Au sein de ce travail, nous nous sommes intéressés à l'étude des propriétés physiques des paires moléculaires Fe/Co, avec l’objectif de comprendre les mécanismes du phénomène de transfert d'électrons. Le chapitre I contient les exemples les plus représentatifs des réseaux de coordination d'analogues de bleu de Prusse et de leurs analogues moléculaires Fe/Co, en se concentrant sur les techniques utilisées pour comprendre leurs propriétés photomagnétiques et les stratégies synthétiques employées pour contrôller leur dimensionnalité et obtenir ces analogues moléculaires. Les bases théoriques du transfert d'électron ainsi que la motivation de ce travail sont décrites à la fin du chapitre. Après une introduction sur l’utilisation des briques moléculaires employées au cours de ce travail à travers l’étude de leurs potentiels redox, le chapitre II est consacré à la synthèse et la caractérisation de nouveaux composés dinucléaires à ponts cyanures Fe/Co. Des études structurales, spectroscopiques, magnétiques, photomagnétiques, diélectriques et d’absorption des rayons-X révèlent qu'un transfert d’électron métal-métal peut être déclenché à l'état solide en faisant varier la température et par application de la lumière. Dans le chapitre III est présenté l'influence de l'environnement des complexes binucléaires Fe/Co, à savoir les contre-ions, sur le transfert d’électron thermo- et / ou photo-induit à l'état solide. Enfin le chapitre IV porte sur la possibilité de transférer le phénomène de transfert d'électron des paires Fe/Co étudiées de l'état solide à la solutionThis thesis is dedicated to the synthesis of new dinuclear cyanido-bridged Co/Fe complexes, which mimics on a single molecule the original properties of the coordination network of Prussian Blue Analogues AxCo[Fe(CN)6]y•nH2O (A= alkaline ions), i.e. intramolecular thermal and photo-induced electron transfer in the solid state. We focus on the study of the physical properties of the simplest Fe/Co PBA, a dinuclear complex, with the hope to understand the fundamental concepts of this fascinating phenomenon. Chapter I contains the most representative examples of Fe/Co PBAs, focusing on the synthetic strategies employed in order to obtain Fe/Co PBAs of different dimensionalities and the techniques used to understand their photomagnetic properties. The theoretical background of the electron transfer phenomenon and the motivation of our work are described in the end of the chapter. After introducing the choice of the building blocks used in this work through the study of their redox potential properties, chapter II is devoted to the synthesis and the characterization of a novel dinuclear Fe/Co cyanido-bridged complex, which exhibits metal-to-metal electron transfer properties in solid state triggered by temperature and light. The ET phenomenon has been also studied by X-ray absorption spectroscopy and dielectric measurements. In Chapter III is illustrated the influence of the environment content of the dinuclear Fe/Co complexes, such as the counter ions, on the occurrence of the thermally and/or photo-induced electron transfer in solid state, thus highlighting the versatility of these molecular materials. Finally in chapter IV, the possibility of transferring the electron transfer phenomenon of the studied Fe/Co pairs from solid state to solution is investigated
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Calancea, Sergiu. "Synthèse et caractérisations de nouveaux complexes binucléaires à transfert d’électron de type {Fe(µ-CN)M} (M = Fe, Mn, Co)." Thesis, Bordeaux 1, 2013. http://www.theses.fr/2013BOR14802/document.
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L’une des grandes directions de recherche dans la chimie moderne est la synthèse et l’étude denouveaux composés « commutables » capables de modifier leurs propriétés sous l’effet de stimuli extérieurs (température, lumière, champ magnétique ou électrique…). Ces systèmes peuvent stocker une information à l’échelle moléculaire. Dans ce contexte, parmi les systèmes les plus étudiés en chimie de coordination figurent les réseaux et les analogues moléculaires du bleu de Prusse. Cette thèse est dédiée à la synthèse et aux caractérisations de nouveaux analogues moléculaires du bleu de Prusse à transfert d’électron de type {Fe(µ-CN)M} (M = Fe, Mn, Co). Dans le premier chapitre sont présentées les familles de composés commutables à transfert d’électron par ordre décroissant de leur dimensionnalité, des systèmes 3D vers des systèmes discrets 0D. Le deuxième chapitre regroupe la synthèse et les caractérisations structurales, spectroscopiques, magnétiques, et électrochimiques de complexes-précurseurs de type [MII(LN5)]2+ et [FeIII(LN3/LN2)(CN)n]- (n = 2, 3) (LN5, LN3, LN2 étantdes ligands azotés penta-, tri- ou bidentes, respectivement) qui seront ensuite utilisés dans la synthèse des composés binucléaires. Le troisième chapitre présente la synthèse et les études structurales,spectroscopiques, magnétiques, optiques et électrochimiques de quatre nouveaux composés binucléaires paramagnétiques {FeIII(µ-CN)MII} (MII = Fe, Co). Enfin, le quatrième chapitre se focalise sur la synthèse et les propriétés spectroscopiques, magnétiques, photomagnétiques et électrochimiques de trois nouveaux complexes binucléaires diamagnétiques {FeII(µ-CN)CoIII} à transfert d’électronOne of the main research directions of modern chemistry is the synthesis and study of new switchablecompounds which can change their properties under external stimuli (temperature, light, magnetic orelectric field…). These systems can store the information at the molecular level. In this contextamongst the most studied systems in coordination chemistry are the 3D networks and the molecularPrussian blue analogs. This thesis deals with the synthesis and characterizations of new{Fe(µ-CN)M} (M = Fe, Mn, Co) molecular Prussian blue analogs. In the first chapter electrontransfer compounds are described in order of decreasing of their dimensionality, from 3D to thediscrete 0D systems. The second chapter describes the synthesis and structural, spectroscopic,electrochemical and magnetic characterizations of [MII(LN5)]2+ precursors (MII = Fe, Mn, Co) and[FeIII(LN3/LN2)(CN)n]- (n = 2, 3) (LN5, LN3, LN2 - nitrogen-based penta-, tri- and bi-dentate ligands,respectively), which are used in the synthesis of the binuclear complexes. Chapter three presents thesynthesis and structural, magnetic, spectroscopic and electrochemical studies of four binuclearparamagnetic {FeIII(µ-CN)MII} complexes (MII = Fe, Co). Chapter four is focused on the synthesisand spectroscopic, magnetic, photomagnetic and electrochemical properties of three binucleardiamagnetic {FeII(µ-CN)CoIII} electron transfer complexes
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Rios, dos Santos Jalila. "Partição de matróides, conjuntos co-geradores e bridget-it." Universidade Federal de Pernambuco, 2003. https://repositorio.ufpe.br/handle/123456789/7368.
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Previous issue date: 2003Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
O trabalho aqui apresentado consiste no estudo e plicação da teoria relacionada com conjuntos co-geradores de uma matróide, desenvolvida por Alfred Lehman e Jack Edmonds, num jogo chamado Bridge-it. Para tanto, exibimos um algoritmo que encontra, dada uma matróide, um subconjunto maximal de seus elementos, A0, o qual pode ser particionado em k subconjuntos independentes co-geradores, disjuntos, e geradores de A0. Este conjunto A0 está fortemente relacionado com as estratégias dos jogadores
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Colson-Duparchy, Alexia. "Bridges, hoops and pools : international film co-production : the interface between culture and trade." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=78210.
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International film co-productions are sometimes thought of by the Americans as a form of financing providing the U.S. with the ability to sell works to its most important export market, Europe. Europe prefers thinking of it as way to provide its market with works that reflect European culture and ideals. This thesis questions the reality of such a statement, using the examples of the EU, the U.S. and Canada.The author first explains the mechanism of co-production within the framework of a presentation of the methods of film financing. Follows a twofold discussion on the current nature of international co-productions, on both the international and national levels.
A considerable portion of this work examines the terms of the debate about the interplay between culture and trade. As an instrument used in the audiovisual industry, therefore strongly connected to cultural industries, international co-production is indeed an ideal model to represent the tensions existing between culture and global trade. This thesis sets international co-production up as a symbol of the interface between culture and trade.
Follows a debate on the congruity of the existing global and regional trade agreements for the protection of a culture always weaker in its diversity and propagation. With the prospect of the imminent phasing out of the sectoral exemptions allowed by the GATS, the inadequacy of the NAFTA cultural exemption and current quota policy systems, what would be best to calm down the tensions between culture and trade? Three solutions are discussed here: the New International Instrument on Cultural Diversity; a powerful competitor to the American majors such as Vivendi-Universal, and the technique of co-ventures.
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Houde, Nicolas. ""Experimenting with what will become our traditions": adaptive co-management as a bridge to an Atikamekw Nehirowisiw post-treaty world in Nitaskinan, Canada." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=104589.
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This thesis examines whether transitioning from current co-management approaches to an adaptive co-management approach would resolve some of the problems experienced in current treaty negotiations contexts between Canadian First Nations and the state government. It first identifies how adaptive co-management would be an improvement on existing treaty processes. Secondly, it examines how the co-existence of different knowledge systems and cultural change can be addressed in an adaptive co-management process. Finally, the thesis identifies the preconditions needed in order to build organisations for adaptive treaties. The case of the Atikamekw First Nation (central Quebec, Canada) treaty negotiations serves as a case study to meet these research objectives. Research results identify adaptive co-management as a suitable approach for creating treaties that are closer to First Nations' needs by focusing on learning and the on-going renewal of a people-to-people relationship. This approach departs from current static and bureaucratic models of treaty making, which concentrate on structural aspects of co-management and the extinguishment of Aboriginal rights. The research identifies adaptive co-management as a potential catalyst for the revitalization of Aboriginal cultures by reporting on the current transformation of the Atikamekw First Nation traditional institutions of governance in order to increase their participation in natural resource management decision-making processes. It also conveys that the Atikamekw aim towards having a decision-making system rooted in the past, with the territorial chief at its core, but yet future-oriented, not fixed in time, and departing from its original form, therefore highlighting the need for flexible and adaptive organisations for the co-management of the land.Cette thèse détermine si une approche de cogestion adaptative peut ou non résoudre quelques uns des problèmes actuellement rencontrés lors de négociations de traités entre premières nations du Canada et l'état. La thèse identifie dans un premier lieu la façon dont la cogestion adaptative présenterait une amélioration par rapport aux traités actuels. Deuxièmement, elle examine la façon dont la coexistence de différents systèmes de savoir et le changement culturel peuvent être pris en compte dans un processus de cogestion adaptative. Finalement, la thèse identifie les préconditions requises pour la mise sur pied d'organisations de cogestion dans un contexte de traité adaptatif. Pour atteindre ces objectifs, c'est le cas de la négociation territoriale de la nation atikamekw (Quebec, Canada) qui est étudié. Les résultats de recherche indiquent que la cogestion adaptative est une approche appropriée afin d'en arriver à des traités qui sont plus près des besoins des premières nations en valorisant l'apprentissage en continu et le renouvellement continuel d'une relation de peuple-à-peuple. Cette approche se distingue des modèles actuels de traités, qui tendent à être statiques et bureaucratiques, se concentrant sur les aspects structuraux de la cogestion et l'extinction des droits ancestraux. La recherche souligne qu'une approche adaptative de la cogestion a un potentiel de catalyseur pour la revitalisation des cultures autochtones. Ceci est illustré par le processus de transformation des institutions de gouvernance territoriale ayant présentement cours chez les Atikamekw. La thèse démontre que les Atikamekw désirent construire un système décisionnel ancré dans le passé, centré sur le chef de territoire et la famille, mais tourné vers l'avenir, évolutif et différent de sa forme originale.
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Yang, Kaiyuan. "Substitution Chemistry of the Cobalt Complexes [Co₂(CO)₆(PhC≡CR) (R=Ph, H) and PhCCo₃(CO)₉] with the Diphosphine Ligands [Bis(diphenylphosphino)maleic Anhydride (BMA) and (Z)-Ph₂PCH=CHPPh₂]. Reversible Chelate-to-Bridge Diphosphine Ligand Exchange, Phosphorus-Carbon Bond Cleavage and Phosphorus-Carbon Bond Formation." Thesis, University of North Texas, 1994. https://digital.library.unt.edu/ark:/67531/metadc279206/.
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The tricobalt cluster PhCCo3(CO)9 (1) reacts with the bidentate phosphine ligand 2,3-bis(diphenylphosphino)maleic anhydride (bma) in the presence of added Me3NO to give the diphosphine-substituted cluster PhCCo3(CO)7(bma) (2). Cluster 2 is unstable in solution, readily losing CO to afford Co3(CO)6[(μ2-η2/η1-C(Ph)C=C(PPh2)C(O)OC(O)](μ2-PPh2) (3) as the sole observed product. VT-31P NMR measurements on cluster 2 indicate that the bma ligand functions as both a chelating and a bridging ligand. At -97 °C, 31P NMR analysis of 2 reveals a Keq of 5.7 in favor of the bridging isomer. The bridged bma cluster 2 is the only observed species above -50°C. The solid-state structure of 2 does not correspond to the major bridging isomer observed in solution but rather the minor chelating isomer. The conversion of 2 to 3 followed first-order kinetics, with the reaction rates being independent of the nature of the reaction solvent and strongly suppressed by added CO, supporting a dissociative loss of CO as the rate-determining step. The activation parameters for CO loss were determined to be ΔH≠ = 29.9 ± 2.2 kcal/mol and ΔS≠ = 21.6 ± 6 eu.
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Florêncio, Cláudia. "Learning to bridge conservation and development: A case study of the Environmental Monitors Programme in Kruger to Canyons Biosphere Reserve." Thesis, Stockholms universitet, Stockholm Resilience Centre, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-131843.
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We live in a world that faces several social and environmental problems and achieving sustainable development in contexts where it is necessary to alleviate poverty without eroding the capacity of the ecosystems to support future generations is challenging. Therefore, fostering sustainable development requires enabling both society and environment to cope with disturbances, adapt to and shape change (resilience). Literature suggests that adaptive co-management practices are appropriate for building resilience and fostering sustainable development. Additionally, studies have highlighted the role of bridging organizations in coordinating and facilitating adaptive co-management. However, adaptive co-management has not been studied in poverty contexts. This thesis aims to understand what the main tasks of bridging organizations are, and how they facilitate and stimulate adaptive co-management in poverty contexts and their role in nurturing sustainability. The Environmental Monitors Programme of the Kruger to Canyons Biosphere Reserve was chosen as a case-study. Biosphere reserves are considered learning sites for sustainable development. The programme was studied through the lenses of a bridging organization. Semi-structured interviews and participatory observation with stakeholders identified: 1) the importance of existing networks and collaborations; 2) monitoring contribution to the identification of social and environmental issues, experimentation contribution to the implementation of sustainable harvesting practices; 3) environmental education combined with social learning lead to community empowerment and adaptive responses that e.g. address erosion; 4) environmental monitors have a crucial role in linking organizations and communities; 5) challenges related to low income settings include communities’ basic needs. This study illustrates the need to address both social and ecological problems in a concerted manner, by capacitating and empowering communities while conserving the environment. Additionally, points out the need of studying alternative co-management strategies that give focus on different priorities regarding stakeholders’ interests and the influence of power in decision-making in poverty contexts.
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Cheng, Yaw-Chung, and 鄭堯中. "Substitution Reactions of Phosphido bridged complexes Cp(CO)2W(PPh2)W(CO)5." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/49637863011436766432.
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Hsu, fu-yung, and 徐富勇. "Synthesis，Structure and Reaction of Metal-Metal Bonded Heterobimetallic Phosphido-Bridged complex (CO)3Fe(μ-PPh2)2W( CO)4." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/77111746797493191746.
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Woollam, Stephen Farring. "The redox and co-ordination chemistry of some dinuclear diphosphazane- bridged derivatives of ruthenium." Thesis, 1991. http://hdl.handle.net/10413/11307.
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Yang, Yaw-Cherng, and 楊曜誠. "Studies of Nucleophilic Substitution on AreneCr(CO)3 : Synthetic and Mechanistic Approaches to Bimetallic Compounds Bridged by Cyclopentadienyl Related Nucleophiles." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/32440066249039578608.
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"Synthesis and reactions: (u-h)(u-ph(2)p(ch(2))(n)ph(2)p)mo(co)(8)(-) anions and axial replacement in na(2)pt(2)(u-po(4)h)(4)(h(2)o)(2) (binuclear molybdenum carbonyl anions bridged by hydride and bidentate phosphine ligands, tetrakis u-phosphato diplatinum(iii) complexes, sodium, platinum)." Tulane University, 1986.
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Synthesis and Reactions of Binuclear Molybdenum Carbonyl Anions Bridged Both by Hydride and Bidentate Phosphine Ligands, and Axial Ligand Replacement in Tetrakis u-Phosphato Diplatinum (III) Complexes Reactions of Et(,4)N('+) and Ph(,4)P('+) salts of u-HMo(,2)(CO)(,10)('-) with diphos ligands in refluxing THF yielded salts of u-H-Mo(,2)(CO)(,8)(Ph(,2)P- (CH(,2))(,n)PPh(,2))('-), n = 1, 2 and 4. X-ray crystal structure analysis of the n = 1 and n = 4 derivatives shown an overall bent, staggered config- uration in each case with a P-Mo-Mo-P torsion angle of 21(DEGREES) for n = 1 and 42(DEGREES) for n = 4 Chemical reactions of these supported bridging hydrides include protonation to remove H('-) and open up adjacent coordination sites, capturable by other ligands such as diars, diphos, acetonitrile, t-butyl-isocyanide, and carbon monoxide. The u-HMo(,2)(CO)(,8)Ph(,2)PCH(,2)PPh(,2)('-) anion catalytically decomposes formic acid, producing H(,2) and a spectroscopically observable u-formato binuclear complex anion which slowly extrudes CO(,2) and reforms the original u-H binuclear anion. Photolysis of u-HMo(,2)(CO)(,8)Ph(,2)PCH(,2)PPh(,2)('-) in the presence of Ph(,2)PCH(,2)PPh(,2) leads to the triply bridged binuclear anion, u-HMo(,2)- (CO)(,6)(Ph(,2)PCH(,23)Ph(,2))(,2)('-) The diplatinum(III) complex Pt(,2)(u-PO(,4)H)(,4)(H(,2)O)(,2) ('2-) reacts with halide ions X('-)(X = CL, Br) to give first Pt(,2)(u-PO(,4)H)(,4)X(H(,2)O) ('3-) and then Pt(,2)(u-PO(,4)H)(,4)X(,2) ('4-). The reaction establishes an equilibrium situation between the three complexes: (UNFORMATTED TABLE FOLLOWS) K(,1) Pt(,2)(u-PO(,4)H)(,4)(H(,2)O)(,2)('2-) + X('-) Pt(,2)(u-PO(,4)H)(,4)X(H(,2)O)('3-) k(,2) K(,3) Pt(,2)(u-PO(,4)H)(,4)X(H(,2)O)('3-) + X('-) Pt(,2)(u-PO(,4)H)(,4)X(,2)('4-) k(,4)(TABLE ENDS) Using pseudo first order conditions in halide ion at 25(DEGREES)C we have used a biphasic analysis to evaluate the rate constants. Under comparable conditions we measured the equilibrium constants Reactions of diplatinum(III) complex Pt(,2)(u-PO(,4)H)(,4)-(H(,2)O)(,2)('2-) with ligands L (L = I('-), N(,3)('-), NH(,3), pyridine, pyrazine, guanine, cytosine, S-methyl-L-cysteine, methionine, 2,2('-)-thiodiethanol, thiodipropionic acid, tetrahydrothiophene, thioacetamide, thiourea, mercaptopropi- onic acid, and homo L-cysteine) in aqueous solution yield Pt(,2)(u-PO(,4)H)(,4)L(,2) ('-n) where n = 2 for neutral ligands and n = 4 for anionic ligands. All of these compounds where characterized by UV-Vis, ('31)P NMR, IR or by X-ray crystallographyacase@tulane.edu
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(6954347), Susannah Dawn Cox Banziger. "Synthesis and Structural Studies of Donor-Bridge-Acceptor Complexes Based on Co(III)(cyclam) Acetylides." Thesis, 2019.
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Obtaining a greater understanding of photo-induced electron-transfer (PET) processes is key to synthesizing photovoltaic materials with enhanced efficiency. Gaining knowledge about the structure property relationship in photo-active donor-bridge-acceptor (D-B-A) dyads will help to optimize electronic and photoelectronic materials. Metal acetylide complexes have attracted increasing interest for their potential applications as building blocks for electronic and photoelectronic materials. Their unique υ(C≡C) (2000-2100 cm-1) allows for selective excitation, making them an appealing target for attenuating PET processes across a metal acetylide backbone. The following topics will be discussed: i.) an overview of M(cyclam′) alkynyl chemistry, where M = Cr, Fe, Co, or Ni, with a focus on reactivity and spectroscopy, ii.) selective synthesis of dissymmetric species, utilizing a CoIII(cyclam) (1,4,8,11-tetraazacyclotetradecane) alkynyl bridge, iii) synthesis and characterization of metal alkynyl D-B-A dyads trans- [R'2N-4-C6H4C2-CoIII(cyclam)-Cn-NAPR]+ (n = 2 or 4), where the chromophore acceptor is NAPiPr (N-isopropyl-1,8-napthalimide) and the putative donor is -C6H4-4-NR'2 (R' = Me or Ph-4-OMe), iv.) design and synthesis of D-B-A derivatives, alter NAPR (R = mesityl, methyl, 1-ethylpropyl, 2-ethylhexyl, or octyl) to tune reactivity and crystallinity, v.) electronic and spectroscopic influence the bridging center on A, and vi.) effect of η2 coordination of MX2 (MX2 = CuCl2 or Ag(NO3)2) to the alkyne bridge on electron transfer.