The goal of the work described in this dissertation was to investigate the structure of metal phosphonate frameworks which were composed of conforma-tionally flexible ligands. This goal was achieved through investigating new syn-thetic techniques, systematically changing structural aspects (i.e. chain length), and conducting in situ X-ray diffraction experiments under non-ambient condi-tions. First, the use of ionic liquids in the synthesis of metal phosphonates was in-vestigated. Reaction systems which had previously been studied in purely aqueous synthetic media were reinvestigated with the addition of a hydrophobic ionic liq-uid to the reaction. Second, the structural diversity of zinc alkylbisphosphonates was investigated through systematically varying the chain length and reaction conditions. Last, the structural changes associated with externally applied stimuli (namely temperature and pressure) on conformationally flexible metal phospho-nates were investigated. Elevated temperature was used to investigate the structur-al changes of a 1-D cobalt chain compound through three stages of dehydration and also applied pressures of up to 10 GPa were used to probe the structural resili-ence of two zinc alkylbisphosphonate materials under. The iminobis(methylphosphonic acid) type ligands are a good example of a small, simple, conformationally flexible ligand. There are three distinct different structural types, utilizing this ligand with cobalt metal, described in the literature, all of which contain bound or solvated water molecules. The addition of a hydrophobic ionic liquid to an aqueous synthesis medium resulted in new anhydrous compounds with unique structural features. Systematic investigations of zinc alkylbisphosphonate materials, construct-ed with three to six carbon linker ligands, resulted in four new families of com-pounds. Each of these families has unique structural features which may prove in-teresting in future applications developments. Importantly, it is shown that wheth-er the chain length is odd or even plays a role in structural type although it is not necessarily a requirement for a given structural type; furthermore, chain length itself is not strictly determinative of structural type. Dehydration in a cobalt phosphonate was followed via in situ single crystal X-ray diffraction. The compound goes through a two-stage dehydration mecha-nism in which the compound changes from a 1-D chain to a 2-D sheet. This pro-cess is reversible and shows unique switchable magnetic properties. The high pressure studies of an alkyl chain built zinc metal phosphonate showed that the chains provide a spring-like cushion to stabilize the compression of the system allowing for large distortions in the metal coordination environment, without destruction of the material. This intriguing observation raises questions as to whether or not these types of materials may play a role as a new class of piezo-functional solid-state materials.

Le fait qu'un composé métal-organique contienne à la fois une partie organique et une partie inorganique, rend ces systèmes hautement modulables, de la dimensionnalité de leur structure aux propriétés obtenues. Ainsi, la chimie de coordination a été axée sur la synthèse de nouveaux matériaux à base de cations 3d et 4f, liés par des ligands organiques avec des groupes fonctionnels de nature chimique différente, ce qui permet de trouver à ces matériaux intéressants des propriétés telles que la luminescence, l'optique non linéaire et le magnétisme. En outre, la synthèse de composés métal-organique de dimensionnalité supérieur a été dominé par les longues durées de réaction, en plus de l'utilisation de solvants organiques exposés à des conditions de température et supérieures à celles utilisées dans des procédés de synthèse classique pression. Cependant, au cours des dernières années, l'intérêt s'est accru dans le développement de nouvelles techniques de synthèse avec des temps de réaction plus courts et plus favorables à l'environnement, tels que la mécanochimie et la sonochimie. Dans cette thèse, nous présentons la synthèse, la caractérisation structurale et optique de neuf composés de coordination basés sur le liant d'imidazole-4-acide acrylique. Les composés sont classés en deux types: (1) sur la base des cations nd, à l'intérieur qui sont les précurseurs du type [M(HIA)2(H2O)4] (M = CuII, NiII, CdII et ZnII), obtenu par synthèse mécanochimique, et le polymère de coordination {[Cd(H2IA)(HIA)(H2O)2]2∙H2O(NO3)2}n obtenu par sonochimique; et (2) des composés hétérométallique nd/4f, qui sont basées sur la Cu(II)/Eu(III), Cu(II)/Gd(III), Cu(II)/Ce(III) et cations Cd(II)/Ce(IV), tous obtenus par synthèse sonochimique. Il est à noter que les composés basés sur les cations Cu(II)/Ln(III) ont également été caractérisés magnétiquement. De plus, une famille de composés à base de Ni(II)/Ln(II), obtenue par synthèse structurale est rapportée. / The fact that metal-organic compound contains an organic and an inorganic part, makes these systems highly modulable, from the dimensionality of their structure to the properties that are obtained. For this reason during the last time, the coordination chemistry has been focused on the synthesis of new materials based on 3d and 4f cations, linked through organic ligand with functional groups of different chemical nature, which contribute to obtain new materials with interesting properties such as luminescence, non-linear optics and magnetism, among others. On the other hand, the synthesis of metal-organic compounds of greater dimensionality has been dominated by long reaction times, using organic solvents exposed to conditions of temperature and pressure higher than those used in traditional synthesis methods. However, the interest for new synthetic techniques with shorter reaction times and more friendly to the environment, such as mechanochemistry and sonochemistry has grown in last years. In this thesis, are reported the synthesis, structural and optical characterization of nine coordination compounds based on the imidazole-4-acrylic acid ligand. The compounds are classified into two types: (1) based on nd cations, which are the precursors of the type [M(HIA)2(H2O)4] (with M = CuII, NiII, CdII and ZnII), obtained by mechanochemical synthesis, and also the coordination polymer {[Cd(H2IA)(HIA)(H2O)2]2·H2O(NO3)2}n obtained by sonochemistry; and (2) nd/4f heterometallic compounds obtained by sonochemical synthesis, which are based on the CuII/EuIII, CuII/GdIII, CuII/CeIII and CdII/CeIV cations. It should be noted that the compounds based on the CuII/LnIII cations were also magnetically characterized. Additionally, a family of compounds based on NiII/LnII, obtained by structural synthesis is reported. Although, the H2IA ligand does not participate in the final product, the compounds are considered novel from the structural point of view, because the Ln2+ cation, had stabilized only in organometallic compounds until now. Finally, it is important to highlight that the thesis work presented has been carried out within the framework of a co-supervision between the Université de Rennes 1, France, and the Andrés Bello University, Chile, for which two stays were made in France, with six months of duration each one. The results presented were obtained in Laboratoire ISCR Institut des Sciences Chimiques in Rennes, France, and in the Laboratorio de Compuestos Polimetálicos, Chile.

Ce mémoire est consacré à la conception et la caractérisation de molécules, matériaux et dispositifs électroniques commutables incorporant le système photochrome diméthyldihydropyrène (DHP) / cyclophanediène (CPD). La première partie est dédiée à la synthèse et à la caractérisation de photochromes originaux basés sur l'unité diméthyldihydropyrène. En particulier, la modification chimique de ce motif par des groupements électroattracteurs de type pyridinium induit une nette amélioration des cinétiques de conversion photoinduites tout en constituant une unité aisément fonctionnalisable. Dans une seconde partie, le motif photochrome est associé à des complexes métalliques dérivés du ligand terpyridine qui confèrent des propriétés rédox à l'architecture moléculaire. Ces assemblages sont mis en œuvre pour la conception de films minces organisés obtenus par auto-assemblage de métallopolymères sur des surfaces solides. Les complexes et les films étudiés possèdent des propriétés photochromes et une activité rédox particulièrement prometteuses pour la conception de matériaux et dispositifs moléculaires multicommutables. Enfin, nous présentons l'étude de la conductance des isomères DHP et CPD. Un dispositif électronique à molécule unique a ainsi été mis en œuvre en utilisant le motif photochrome fonctionnalisé par deux unités pyridine, utilisées comme fonctions d'ancrage dans le dispositif. Il apparaît que l'isomère DHP possède une conductance d'environ quatre ordres de grandeur supérieurs à celle de l'isomère CPD correspondant. Ces deux états peuvent être commutés de manière très reproductible par application de stimulus optiques et thermiques. / This thesis is devoted to the design and characterization of switchable molecular systems (molecules, materials and electronic devices) incorporating the dimethyldihydropyrene / cyclophanediene (DHP/CPD) photochromic couple. The first part deals with the synthesis and characterization of original photochromic molecules based on the dimethyldihydropyrene unit. In particular, the chemical functionalisation of these molecular systems with electron-withdrawal pyridinium groups leads to an improvement of the kinetics of photo-induced conversion while providing an easily functionalizable unit, for example with metal cations complexing units. In the second part, the photochromic core is covalently linked with metal complexes based on terpyridine derivatives, conferring redox-active properties to the molecular architecture. These assemblies are applied for the design of organized thin films obtained by self-assembly of metallopolymers on solid surfaces. The model complexes and films display photochromic properties and redox activity particularly promising for the design of responsive materials and molecular devices. Finally, we present the study of the conductance of the isomers DHP and CPD. A single molecule electronic device in which individual molecules are utilized as active electronic components has been implemented using the photochromic group functionalized with two pyridine units, used as anchoring functions. It appears that the DHP isomer has a conductance of about four orders of magnitude higher than the corresponding isomer CPD. These two states can be switched very reproducibly and reversibly upon application of optical and thermal stimulus.

Orientador: Prof. Dr. Dalmo Mandelli / Dissertação (mestrado) - Universidade Federal do ABC. Programa de Pós-Graduação em Ciência e Tecnologia/Química, 2017. / A oxidação catalítica de hidrocarbonetos continua sendo uma atividade em plena expansão. Além da abundância dessa classe de compostos, os hidrocarbonetos são substratos relativamente baratos para a síntese de vários produtos de oxidação importantes e de alto valor agregado. Entretanto, esse tipo de reação é dificultada devido à pouca reatividade dos hidrocarbonetos, tornando-se um desafio sua aplicação em sínteses diretas de produtos oxigenados em condições relativamente brandas. Na indústria, processos que envolvem a oxidação de alcanos são efetuados com baixas conversões (muitas vezes não excedendo 10%), para se minimizar a sobreoxidação dos produtos formados que são mais reativos que o substrato inicial. Assim, vários trabalhos têm sido realizados no sentido de se desenvolver novos sistemas catalíticos eficientes para oxidação seletiva, com a finalidade de se obter processos que levem a quantidade cada vez menor de subprodutos e resíduos de reação. No presente trabalho, foi proposto um novo sistema catalítico para a oxidação de hidrocarbonetos saturados e insaturados por H2O2, baseados em polímeros de coordenação de Cu (II) com ligantes de dicarboxilatos e aminoálcoois. De acordo com os resultados, os compostos de coordenação mostraram-se ativos na oxidação dos substratos testados, com um rendimento de até 22% para os produtos de oxidação do cicloexano. Também são capazes de catalisar a oxidação de cicloexeno e limoneno resultando na geração de diferentes produtos de oxidação com rendimentos totais de cerca de 20%. Na oxidação do cicloocteno foi observado a formação de epóxido, o que permitiu confirmar a possível formação desse composto como intermediários na oxidação do cicloexeno. A oxidação do n-heptano é menos eficiente, levando à formação de álcoois isoméricos como principais produtos com uma razão de C(1): C (2): C(3): C(4) = 1,0:5,5:5,5:5,0, o que permitiu sugerir que os mecanismos de reação ocorrem via radicais livres que operam com a participação de radicais hidroxila como principal espécie oxidante. / Catalytic oxidation of hydrocarbons continues to be a booming activity. In addition to the abundance of this class of compounds, hydrocarbons are relatively inexpensive substrates for the synthesis of several high value added oxidation products. However, this type of reaction is difficult due to the low reactivity of the hydrocarbons, making it a challenge to apply them in direct syntheses of oxygenated products under relatively mild conditions. In industry, processes involving oxidation of alkanes are carried out with low conversions (often not exceeding 10%), to minimize the over-oxidation of the formed products that are more reactive than the initial substrate. Thus, several studies have been carried out in order to develop new efficient catalytic systems for selective oxidation of these hydrocarbons, in order to obtain processes that lead to a decreasing amount of by-products and reaction residues. In the present work, new catalytic systems was proposed for the oxidation of saturated and unsaturated hydrocarbons by H2O2 based in Cu (II) coordination polymers built with dicarboxylates and aminoalcohols molecules. According to the results, the coordination compounds were active in the oxidation of the tested substrates, with a total yield of up to 22% for the oxidation products of cyclohexane. They are also capable of catalyzing the oxidation of cyclohexene and limonene resulting in the generation of different oxidation products with total product yields of nearly 20%. In the oxidation of the cyclooctene the epoxide formation was observed, which allowed to confirm the hypothesis of formation of this compound as intermediate in the oxidation of cyclohexene. The oxidation of n-heptane is less efficient, leading to the formation of isomeric alcohols as major products with a ratio of C (1):C (2):C (3): C(4) = 1.0:5.5:5.5:5.0, suggesting that the mechanisms of reaction occur through free radicals that operate with the participation of hydroxyl radicals as the main oxidizing species.

Polímeros de coordenação têm atraído a atenção de pesquisadores na última década por conta de sua incrível versatilidade e virtualmente infinito número de possibilidades de combinação de ligantes orgânicos e centros metálicos. Estes compostos normalmente herdam as características magnéticas, eletrônicas e espectroscópicas de seus componentes base. Entretanto, apesar do crescente número de trabalhos na área, ainda são raros os polímeros de coordenação que apresentem condutividade elétrica. Para este fim, utilizou-se a N,N\'-bis(4-piridil)-1,4,5,8-naftaleno diimida, ou NDI-py, que pertence a uma classe de compostos rígidos, planares, quimicamente e termicamente estáveis e que já foram extensamente estudados por suas propriedades fotoeletroquímicas e semicondução do tipo n. O primeiro polímero de coordenação sintetizado, MOF-CoNDI-py-1, indicou ser um polímero linear, de estrutura 1D. O segundo, MOF-CoNDI-py-2, que conta com ácido tereftálico como ligante suporte, é um sólido cristalino com cela unitária monoclínica pertencente ao grupo espacial C2/c, determinado por difração de raios-X de monocristal. A rede apresenta um arranjo trinuclear de íons Co(II) alto spin com coordenados em uma geometria de octaedro distorcido, enquanto os ligantes NDI-py se encontram em um arranjo paralelo na estrutura, em distâncias apropriadas para transferência eletrônica. Com o auxílio de cálculo teóricos a nível de DFT, foi realizado um estudo aprofundado dos espectros eletrônicos e vibracionais, com atribuição das transições observadas, tanto para o MOF-CoNDI-py-2 quanto para o ligante NDI-py livre. A rede de coordenação absorve em toda a região do espectro eletrônico analisada, de 200 nm a 2500 nm, além de apresentar luminescência com característica do ligante. Dispositivos eletrônicos fabricados com um cristal do MOF-CoNDI-py-2 revelaram condutividades da ordem de 7,9 10-3 S cm -1, a maior já observada para um MOF. Além de elevada, a condutividade elétrica dos cristais demonstrou-se altamente anisotrópica, sendo significativamente menos condutor em algumas direções. Os perfis de corrente versus voltagem foram analisados em termos de mecanismos de condutividade, sendo melhores descritos por um mecanismo limitado pelo eletrodo to tipo Space-Charge Limited Current, concordando com a proposta de condutividade através dos planos de NDI-py na rede. A condutividade dos cristais também é fortemente dependente de luz, apresentando fotocondução quando irradiado por um laser vermelho, de 632 nm, enquanto apresenta um comportamento fotorresistivo frente a uma fonte de luz branca. Estes resultados, combinados, trazem um MOF em uma estrutura incomum e com elevada condutividade elétrica, modulada por luz, em medidas diretas de corrente. Não existem exemplos conhecidos de MOFs na literatura com estas características. / Coordination polymers have been a major topic in materials science during the past decade, thanks to their versatility and virtually infinite possible combinations between metal centers and organic ligands. These coordination polymers usually inherit the properties of their components, such as magnetic, spectroscopic and electronic characteristics. However, despite the increasing number of research papers in this topic, it is still hard to find coordination polymers featuring electronic conductivity. To achieve that, we used a naphthalene diimide derivative, N,N\'-bis(4-pyridyl)-1,4,5,8- naphthalene diimide or NDI-py, which belongs to a class of rigid, planar, thermally and chemically stable compounds, extensively studied due to their photoelectrochemical properties and their n-type semiconductivity. The first coordination polymer synthesised, MOF-CoNDI-py-1, was an amorphous linear polymer, with a 1D structure. Based on these observations, MOF-CoNDI-py-2 was synthesised by using terephthalic acid as a supporting ligand, and it is a crystalline solid which its monoclinic unit cell belongs to a C2/c space group, as determined by single crystal X-ray diffraction. This network features a trinuclear high-spin Co(II) unit, and each metal ion sits on a distorted octahedra coordination geometry, while the NDI-py ligands sit in a parallel arrangement, with distances suitable for electronic transfers. A detailed study of their vibrational and electronic spectra, supported by DFT calculations, was performed, as well as a full description and assignment of the observed bands. MOF-CoNDI-py-2 absorbs in the whole studied spectral region, from 200 nm to 2500 nm, while it also features a ligand-centered emission spectrum. Electronic devices built around its crystals revealed electric conductivities of 7.9 10 -3 S cm -1, which is, to the best of our knowledge, the highest for a MOF to this date. This conductivity is also highly anisotropic, being significantly less conductive in certain directions. The current versus voltage profiles were analysed in terms of known conduction mechanisms, with best fits when using an electrode-limited Space-Charge Limited Current mechanism, in agreement with the proposition that this conductivity happens through the NDI-py stacking planes. Additionally, this mechanism is influenced by an external light source, being a photoconductor with a red laser, 632 nm, and a photoresistor with a white light. Combined, these results bring a light-modulated, highly conductive MOF material with an unusual structure. As far as we know, there are no similar MOFs in the literature, which makes MOF-CoNDI-py-2 one of a kind.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-05-04T18:30:45Z No. of bitstreams: 1 filipebarradealmeida.pdf: 7947999 bytes, checksum: dc362590639be1c4acb93cdcf62990c9 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-05-17T13:33:19Z (GMT) No. of bitstreams: 1 filipebarradealmeida.pdf: 7947999 bytes, checksum: dc362590639be1c4acb93cdcf62990c9 (MD5) / Made available in DSpace on 2017-05-17T13:33:19Z (GMT). No. of bitstreams: 1 filipebarradealmeida.pdf: 7947999 bytes, checksum: dc362590639be1c4acb93cdcf62990c9 (MD5) Previous issue date: 2016-07-28 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Este trabalho apresenta a síntese e estudo de polímeros de coordenação para adsorção de gases. Especificamente, os compostos apresentados foram sintetizados pela combinação do ligante INH com um dos ligantes H2BDC, H3BTC e H4BTC coordenados aos íons Co2+, Zn2+ e Mn2+, sendo um total de sete compostos. Os compostos Zn-H2BDC e Mn-H2BDC formaram-se como complexos moleculares simples pelos ligantes INH e H2BDC coordenados aos íons Zn2+ e Mn2+, sendo caracterizados pelas técnicas de espectroscopia na região do infravermelho e espalhamento Raman, pela análise elementar (CHN), análise termogravimétrica (TGA e DrTGA) e por difração de raios X por monocristal. Os mesmos apresentaram várias interações intermoleculares diferenciadas e uma rica química supramolecular. Além desses compostos citados, todos os outros cinco compostos se formaram como polímeros de coordenação. Os compostos Co-H2BDC, Zn-H3BTC e Co-H3BTC apresentaram-se como polímeros de coordenação com possibilidade de serem usados em adsorção de gases. O composto Co-H2BDC foi formado pelos ligantes INH e H2BDC com o íon Co2+ e se formou como um polímero de coordenação 2D policatenado, já o composto Zn-H3BTC foi formado pelos ligantes INH e H3BTC e o íon Zn2+ e se formou como um polímero de coordenação 1D. Ambos os compostos foram caracterizados por técnicas usuais de espectroscopia tais como espectroscopia na região do infravermelho e espalhamento Raman, análise elementar (CHN), difração de raios X por monocristais e por policristais, este último com variação de temperatura; cálculos teórico-computacionais e testes de adsorção gasosa pela metodologia B. E. T.. O composto Co-H2BDC apresentou possíveis poros em relação ao eixo cristalográfico c, mas os mesmos não possuíram tamanho suficiente para estabilizar moléculas de gás N2 adsorvido. Além disso, os cálculos teórico-computacionais comprovaram a maior estabilização da estrutura dopada com Li+ e a magnetização da mesma. Para o composto Zn-H3BTC, foi verificado que a estrutura do mesmo não mantem sua cristalinidade com o aumento de temperatura, mas que o mesmo possivelmente não se decompõe na temperatura experimental do teste de adsorção gasosa, sendo que o mesmo apresentou capacidade de adsorção de gases caracteristicamente em multicamadas. O composto CoH3BTC foi formado pelos ligantes INH e H3BTC coordenados ao íon Co2+, formando um polímero de coordenação 2D que se empilham de forma invertida e em pares, formando uma estrutura lamelar com potenciais vazios nas lamelas. Este composto foi caracterizado por técnicas espectroscópicas, análise elementar (CHN), análise termogravimétrica (TGA e DrTGA) e difração de raios X por monocristais. Os compostos Co-H4BTC e Zn-H4BTC formaram-se como polímeros de coordenação 3D e 1D, composto pelos ligantes INH e H4BTC coordenados aos íons Co2+ e Zn2+, respectivamente. Ambos os composto foram caracterizados por técnicas usuais de espectroscopia como IV e espalhamento Raman, análise elementar (CHN) e difração de raios X por monocristais. / This work shows the synthesis and study of gas adsorption of coordination polymers. The compounds were synthetized by the combination of the ligand INH with one of the ligands H2BDC, H3BTC and H4BTC coordinated to Co2+, Zn2+ and Mn2+ ions, being seven compounds overall. The compounds Zn-H2BDC and Mn-H2BDC were formed as molecular complexes by the ligands INH and H2BDC coordinated to Zn2+ and Mn2+ ions, being characterized by spectroscopy techniques such as IR and Raman, elemental analysis (CHN), thermogravimetric analysis (TGA and DrTGA) and by single crystal X ray diffraction. The compounds showed several intermolecular interactions and a rich supramolecular chemistry. Besides the mentioned compounds, five other compounds were formed as coordination polymers. The compounds CoH2BDC, Zn-H3BTC and Co-H3BTC formed as coordination polymers with the possibility to be used in the gas adsorption. The compound Co-H2BDC was formed by the ligands INH and H2BDC with Co2+ ion forming a 2D polycatenated coordination polymer and the compound Zn-H3BTC was formed by the ligands INH and H3BTC with Zn2+ forming a 1D coordination polymer. Both compounds were characterized by spectroscopy techniques as IR and Raman, elemental analysis (CHN), by single crystal X ray diffraction and by polycrystals X ray diffraction, this last one applying temperature variation, by theoretical calculation using computational models and by B. E. T. gas adsorption methodology. It was verified that in the compound Co-H2BDC was formed pores in the axis c direction, but the pores does not have enough size to stabilize N2 gas molecule inside it. Additionally, in the theoretical calculations was confirmed the higher stability of Li-doped structure than the non Li-doped structure and further its magnetization. In the compound Zn-H3BTC was verified that its structure did not keep the crystallinity with increasing in temperature, but it did not decomposes in the experimental temperature to gas adsorption experiment. This compound showed gas adsorption properties in multilayers. The compound Co-H3BTC was formed by the ligands INH and H3BTC coordinated to the Co2+ forming a 2D coordination polymer that piles up in reverse way and in pairs. This configuration formed a lamellar structure and it was characterized by spectroscopy techniques as IR and Raman, elemental analysis (CHN), thermogravimetric analysis (TGA and DrTGA) and by X ray diffraction by single crystal. The compounds Co-H4BTC and Zn-H4BTC showed as 3D and 1D coordination polymers composed by INH and H4BTC ligands coordinated to the Co2+ and Zn2+ ions respectively. Both compounds were characterized by spectroscopy techniques such as IR and Raman, elemental analysis (CHN), by single crystal X ray diffraction.

Ces travaux s'inscrivent dans le cadre général de la conversion et du stockage de l'énergie lumineuse. Ces systèmes nécessitent généralement l'association de plusieurs constituants comme un photo-sensibilisateur couplé à un centre métallique secondaire activable et présentant des propriétés catalytiques. Le verrou principal de ces systèmes réside dans l'efficacité du transfert de charge photo-induit. Afin de progresser dans la compréhension fondamentale du transfert de charge photo-induit, le comportement électrochimique et photo-physique d'espèces moléculaires a été comparé à celui de polymères de coordination analogues.La mise au point d'une voie de synthèse permettant l'accès aux espèces moléculaires bimétalliques via un ligand pontant et à leurs polymères de coordinations analogues a été la première étape de ces travaux. Les études électrochimiques et photo-physiques des espèces moléculaires intégrant un ou deux photo-sensibilisateurs ont permis de mettre en évidence des caractéristiques importantes pour un transfert de charge photo-induit. Ainsi, l'impact de certains aspects de la nature et de la structure des complexes et des ligands (ancillaires et pontants) sur les propriétés physicochimiques a pu être déterminé. La complexation du centre métallique activable (cobalt) aboutit à une chute importante du temps de vie de l'état excité traduisant une communication électronique entre les deux centres métalliques. L'insertion de groupements électro-donneurs sur les ligands ancillaires du photo-sensibilisateur induit un transfert d'électron favorisé vers le second centre métallique. L'étude a ensuite été portée sur les polymères de coordination (PC) analogues. Deux types de PC ont été développés, un premier où les nœuds du réseau sont uniquement des entités photo-sensibilisatrices, le catalyseur étant complexé au ligand organique pontant, un deuxième constitué d'une alternance régulière de nœuds photosensibles et de nœuds catalytiques. Ces composés, de nature amorphe, ont été synthétisés et leurs propriétés photo-physiques ont été étudiées. Enfin, des tests catalytiques de réduction de CO2 et de proton ont été réalisés sur différents composés moléculaires et polymères de coordination. / This work falls within the global project of the light energy conversion and storage. These systems require the association of several molecular constituents as a photosensitizer coupled to a catalyst. In order to improve the fundamental understanding on photo-induced charge transfer, the photo-physical behavior of molecular species was compared to their coordination polymers analogs. The first step of this work was to develop a synthetic pathway leading to bimetallic molecular species through an organic bridging ligand and to their coordination polymers analogs. The electro-chemical and photo-chemical studies of molecular species incorporating one or two photosensitizing units highlight the essential parameters for a photo-induced charge transfer. The effect of the nature and structure of the complexes and the ligands (ancillary ligands and bridging ligands) on physico-chemical properties was studied. Complexation of cobalt induces a significant drop of the excited state lifetime assigned to an electronic communication between the two metallic centers. Incorporation of electro-donating substituents on the ancillary ligands linked to the photosensitizer unit leads to a better electron transfer to the second metal center. Then the study was focussed on the coordination polymer (PC) analogs. Two kinds of PC were synthesized, a first one incorporating only photosensitizing units as nodes, the catalyst being coordinated to the organic ligand, a second one with photosensitizing and catalytic units as nodes. These amorphous materials were synthesized and their photo-physical properties were studied. Finally the first attempts for the photo reduction of CO2and protons were realized on molecular species and coordination polymers.

Due to their high surface areas and structural tunability, porous metal-organic materials, MOMs, have attracted wide research interest in areas such as carbon capture, as the judicious choice of molecular building block (MBB) and linker facilitates the design of MOMs with myriad topologies and allows for a systematic variation of the pore environment. Families of MOMs with modular components, i.e. MOM platforms, are eminently suitable for targeting the selective adsorption of guest molecules such as CO2 because their pore size and pore functionality can each be tailored independently. MOMs with saturated metal centers (SMCs) that promote strong yet reversible CO2 binding in conjunction with favorable adsorption kinetics are an attractive alternative to MOMs containing unstaurated metal centers (UMCs) or amines. Whereas MOMs with SMCs and exclusively organic linkers typically have poor CO2 selectivity, it has been shown that a versatile, long known platform with SMCs, pillared square grids with inorganic anion pillars and pcu topology, exhibits high and selective CO2 uptake, a moderate CO2 binding affinity, and good stability under practical conditions. As detailed herein, the tuning of pore size and pore functionality in this platform has modulated the CO2 adsorption properties and revealed variants with unprecedented selectivity towards CO2 under industrially relevant conditions, even in the presence of moisture. With the aim of tuning pore chemistry while preserving pore size, we initially explored the effect of pillar substitution upon the carbon capture properties of a pillared square grid, [Cu(bipy)2(SiF6)] (SIFSIX-1-Cu). Room temperature CO2, CH4, and N2 adsorption isotherms revealed that substitution of the SiF62- (“SIFSIX”) inorganic pillar with TiF62- (“TIFSIX”) or SnF62- (“SNIFSIX”) modulated CO2 uptake, CO2 affinity (heat of adsorption, Qst), and selectivity vs. CH4 and N2. TIFSIX-1-Cu and SNIFSIX-1-Cu were calculated to exhibit the highest CO2/N2 and CO2/CH4 adsorption selectivites of the series, respectively. Modeling studies of TIFSIX-1-Cu and SIFSIX-1-Cu suggested that the enhancements in low pressure CO2 uptake and CO2 selectivity in the former arose from the stronger polarization of CO2 molecules by TIFSIX-1-Cu. The stronger framework-CO2 interaction at the primary binding site in TIFSIX-1-Cu correlates with the greater electronegativity of the pillar fluorine atoms relative to those in SIFSIX-1-Cu, and in turn to the higher polarizability of Ti4+ vs. Si4+. The effect of tuning pore size upon the carbon capture performance of pillared square grid nets was next investigated. Linker substitution afforded three variants, SIFSIX-2-Cu, SIFSIX-2-Cu-i, and SIFSIX-3-Zn, with pore sizes ranging from nanoporous (13.05 Å in SIFSIX-2-Cu) to ultramicroporous (3.84 Å in SIFSIX-3-Zn). Single-gas adsorption isotherms showed that SIFSIX-2-Cu-i, a doubly interpenetrated polymorph of SIFSIX-2-Cu with contracted pores (5.15 Å), exhibited far higher CO2 uptake, Qst towards CO2, and selectivity towards CO2 vs. CH4 and N2 than its non-interpenetrated counterpart. Further contraction of the pores afforded SIFSIX-3-Zn, a MOM with enhanced CO2 binding affinity and selectivity vs. SIFSIX-2-Cu-i. Remarkably, the selectivity of SIFSIX-3-Zn towards CO2 was found to be unprecedented among porous materials. Equilibrium and column breakthrough adsorption tests involving gas mixtures meant to mimic post-combustion carbon capture (CO2/N2), natural gas/biogas purification (CO2/CH4), and syngas purification (CO2/H2) confirmed the high selectivities of SIFSIX-2-Cu-i and SIFSIX-3-Zn. Gas mixture experiments also revealed that SIFSIX-3-Zn exhibited optimal CO2 adsorption kinetics. Most importantly, the CO2 selectivity of SIFSIX-2-Cu-i and SIFSIX-3-Zn was minimally affected in the presence of moisture. Modeling studies of CO2 adsorption in SIFSIX-3-Zn (experimental Qst ~ 45 kJ/mol at all loadings) revealed strong yet reversible electrostatic interactions between CO2 molecules and the SIFSIX pillars lining the confined channels of the material. Porous materials based upon the non-covalent assembly of discrete MBBs can also exhibit high surface areas and systematically tunable pore environments. Molecular porous material (MPM) platforms have begun to emerge despite the greater challenge of designing such materials in comparison to MOMs. Herein we report the tuning of pore functionality in an MPM platform based upon an extensive hydrogen-bonded network of paddlewheel-shaped [Cu(ade)4L2] complexes (ade = adenine; L = axial ligand). The substitution of Cl axial ligands with inorganic TIFSIX moieties has produced [Cu2(ade)4(TiF6)2], MPM-1-TIFSIX, a variant with enhanced CO2 separation performance and stability. Single-gas adsorption isotherms reveal that MPM-1-TIFSIX exhibits the highest CO2 uptake and CO2 Qst yet reported for an MPM as well as high selectivity towards CO2 vs. CH4 and N2. Modeling studies indicated strong electrostatic interactions between CO2 and the TIFSIX ligands lining the pores of MPM-1-TIFSIX. In addition to dramatically surpassing MPM-1-Cl with regard to CO2 separation performance, MPM-1-TIFSIX exhibits thermal stability up to 568 K and retains its performance even after immersion in water for 24 hrs. Comprehensively, the results presented herein affirm that porous materials featuring inorganic anions and SMCs can exhibit high and selective CO2 uptake, sufficient stability, and facile activation conditions without the drawbacks associated with UMCs and amines, i.e. competitive water adsorption and high regeneration energy, respectively.

Les lanthanides sont de plus en plus étudiés par la communauté scientifique et leur utilisation au sein de dispositifs grand public ne fait que croître. Ces éléments sont en effet connus pour présenter des propriétés magnétiques et de luminescence remarquables. Ils sont alors particulièrement efficaces pour la création de molécules aimants ou de matériaux luminophores. Dans ces travaux de thèse, la synthèse, la cristallogenèse et les caractérisations magnétiques et photo-physiques de nouveaux complexes associant lanthanides et molécules organiques photo-actives sont étudiées. Ces dernières possèdent une conformation « trans » et « cis » et il est possible, grâce à un stimulus lumineux (irradiation UV), de passer de l'une à l'autre. Cette photo-isomérisation induit un changement des propriétés du complexe au sein duquel elles sont présentes. Dans la première partie, quatre nouveaux complexes à base de DyIII, EuIII, TbIII et SmIII sont présentés. Ils sont obtenus grâce à l'association de précurseurs de terres rares et d'une molécule organique dérivée de stilbène : la 4-styrylpyridine. Une forte modulation des propriétés optiques de ces composés induite par l'isomérisation du ligand est observée. Il est mis en évidence que celle-ci a un impact notable sur les propriétés de luminescence des composés et sur leur couleur émise. Dans un second temps, l'influence de cette isomérisation sur les propriétés magnétiques du complexe à base de DyIII est étudiée. La deuxième partie consiste en l'élargissement de l'étude à des molécules photo-actives voisines dans le but de caractériser l'influence du changement de certains groupements chimiques sur les propriétés de photo-isomérisation. Un dérivé de 4-styrylpyridine comportant un groupement diméthyle-amino a ainsi été associé avec un ion DyIII. Un nouveau complexe a été obtenu et ses propriétés magnétiques à l'état solide et en solution étudiées. Parallèlement, l'utilisation d'une nouvelle molécule comportant un groupement diéthyle-amino ainsi qu'une partie azobenzène a donné lieu à l'obtention de deux nouveaux composés à base de DyIII et de TbIII. L'impact de l'isomérisation de ce ligand sur les propriétés luminescentes du complexe à base de TbIII et sur les propriétés magnétiques du complexe à base de DyIII a ensuite été étudié. Dans une troisième partie, les perspectives d'évolution du sujet sont présentées. Une première stratégie consiste à utiliser des solvants moins protonant que le chloroforme afin d'observer une photo-isomérisation plus robuste. Une deuxième stratégie est d'utiliser un ligand magnétique photocommutable. Un radical de la famille des nitronyl nitroxide substitué par un groupement stilbène a ainsi été synthétisé et coordiné à des ions DyIII et TbIII. Leur étude photophysique est commentée. / Lanthanides are more and more studied by the scientific community and their use in devices and operating materials is exploding. These elements are indeed known to exhibit remarkable magnetic and luminescent properties. They are indeed particularly effective for the creation of singles molecule magnets or light emissive materials. In this thesis work, the synthesis, the crystal growth and the magnetic and photo-physical characterizations of new complexes that associates lanthanides and photo-active organic molecules are studied. The latter possess a " trans " and "cis" conformation and it is possible, thanks to a bright UV irradiation stimulus, to switch from one to the other one. This photo-isomerization leads to a modification of the properties of the complex in which they are part of. In the first part, four new complexes with DyIII, EuIII, TbIII and SmIII are presented. They are obtained thanks to the association of precursors of lanthanides and an organic molecule from the stilbene family: the 4-styrylpyridine. A strong modulation of the optical properties of these compounds led by the isomerization of the ligand is observed. It is highlighted that this one has a notable impact on the luminescent properties of these four compounds and on their color emission. Then, the influence of this isomerization on the magnetic properties of the complex with DyIII is studied. The second part consists of the extension of the study in lookalike photo-active molecules. The aim of this work is to characterize the influence of the change of a given chemical group on the photo-isomerization properties. A ligand that is closely related to 4-styrylpyridine containing a dimethyl-amino group, is associated with a DyIII ion. A new complex is obtained and its magnetic properties in the solid state and in solution are studied. Besides, the use of a new molecule containing a diethyl-amino group as well as an azobenzene part gave rise to two new compounds with DyIII and with TbIII. The impact of the isomerization of this ligand on the luminescent properties of the complex with TbIII and on the magnetic properties of the complex with DyIII is then studied. In the third part, the perspectives of evolution of the subject are presented. A first strategy consists is to use less protonatings solvents than the chloroform to observe a stronger photo-isomerization. The second strategy is to use a photo-switching magnetic ligand. A radical of the nitronyl nitroxide family substituted by a stilbene group was synthesized and coordinated to DyIII and TbIII ions. Their photophysical study is commented.

This thesis presents the investigation of magnetism in a selection of low-dimensional systems and its relation to other physical properties, such as superconductivity. The techniques employed are muon spin rotation and pulsed magnetic field magnetisation. The ability of muons to directly probe the local field is used to study SrFeAsF, which is a parent compound of the high-temperature superconducting pnictides. This revealed that the magnetic and structural transitions are separated in this system. I then demon- strate the coexistence of magnetism and superconductivity in NaFeAs for the first time. This discovery is of great interest since the interplay between magnetism and supercon- ductivity is thought to play an important role for high-temperature superconductivity. I further investigate the effect of partially replacing Fe with Co in NaFeAs. I study the ordering and spin reorientation in the Mott insulator Sr₂IrO₄, which has been suggested as a possible high-temperature superconductor. The complex magnetism observed in this system is contrasted to that in related iridates Ca₄IrO₆, Ca₅Ir₃O₁₂ and Sr₃Ir₂O₇. By combining pulsed-field magnetization and low magnetic field experiments with μSR on a series of coordination polymers. I am able to determine the size and direction of the magnetic exchange interaction. I demonstrate how it is possible to adjust the in- teractions by altering the molecular architecture of these Cu-based spin- 1 2 compounds. This is a significant contribution since it will lead to the targeted design of magnetic systems that can be utilized to experimentally test fundamental theories of magnetism.