Crystal Engineering is the design of crystalline material using non-covalent synthesis. Co-crystals are multi-component crystals which are constructed from complementary intermolecular interactions, they are also known as supramolecular complexes. Design of such materials utilises the synthon approach, this involves the understanding of common intermolecular interactions which occur in the crystal packing and is used to design new solids with desired physical properties and chemical properties. Primary amides form supramolecular heterosynthons, these synthons represent an opportunity for a design of multi-component crystals in which one molecule contains a primary amide and a second molecule which is complimentary to the primary amide, usually carboxylic acids. The progress with regards to the screening process for the determination of co-crystals is evident in the literature, In particular, high throughput solution growth methods and solvent drop grinding. The comparison of Isonicotinamide and Benzamide as a co-crystal component has been presented. This study was motivated by the observation that the CSD contains 24 Isonicotinamide and 1 Benzamide co-crystal. The interaction with carboxylic acids is the focus of the work, in particular those which form Isonicotinamide co-crystal are being screened with Benzamide. Our work utilises a ReactArray Microvate to carry out the low throughput solution growth on a matrix of carboxylic acid with Benzamide, this study has been coupled with the Kofler hot stage microscope method which visually aids to screen and view co-crystal phase formation. Crystallisation screens have resulted in the identification of known co-crystal phases of Isonicotinamide and Benzamide, additionally new co-crystal phases have also been identified with Fumaric, 3-hydroxybenzoic acid, Mandelic Acid, 4-Nitrobenzoic Acid and Tartaric Acid. Single crystal structures of the Fumaric and 4-Nitrobenzoic acid have been obtained. In order to develop an understanding of co-crystal formation in Isonicotinamide and Benzamide with our supramolecular library, packing landscape analysis is being undertaken using both the CSD and crystal structures we have obtained. This is undertaken as collaboration with Dr Andy Parkin and Professor Gilmore (University of Glasgow), we have identified that the dSNAP analysis is a way forward for the analysis of how co-crystals pack. The analysis highlighted the subtleties that were present in the packing motifs of the Isonicotinamide co-crystals. In particular the cis and trans orientation of the amide and acid carbonyl to each other and the planar and off planar layer assemblies. All of which are required to maximise the hydrogen bond usage of the components comprising the co-crystals. Further investigations have led to the collaborative project with Syngenta Ltd in the design of a co-crystal screen using a high through-put robot, Crissy® -Automation Platform by Zinsser Analytical, using an extended screen of 16 acid coformers with Isonicotinamide, Benzamide and Nicotinamide the sample have been characterised using a reflectance diffraction method, GADDS. Further analysis of this data involves the use of polySNAP, which has led to further collaboration with Professor Gilmore's group.

Study of thermoresponsive porphyrins and their supramolecular complexes Abstract: We studied the water-soluble artificial compound meso-tetrakis{3,4,5-tris[2-(2-(2- methoxyethoxy)ethoxy)ethoxy]phenyl}porphyrin prepared at NIMS, Japan, using the high-resolution NMR spectroscopy experimental method. We observed its LCST-type phase separation and applied the Flory-Huggins theory of polymer solutions in order to find its phase diagram (binodal and spinodal curves of the phase separation) and we also obtained molar enthalpies, entropies and critical temperatures of its phase separation; from the Flory-Huggins theory we discovered that its molecules form dimers in aqueous solutions. We also studied its host-guest interactions with the S-camphorsulfonic acid; we learned that the porphyrin binds cations and the porphyrin dimers break down when dissolved cations are available for complexation. We observed no phase separation in chloroform. We obtained no proof of the existence of molecular stacks larger than dimers. 1

Crystal Engineering is the design of crystalline material using non-covalent synthesis. Co-crystals are multi-component crystals which are constructed from complementary intermolecular interactions, they are also known as supramolecular complexes. Design of such materials utilises the synthon approach, this involves the understanding of common intermolecular interactions which occur in the crystal packing and is used to design new solids with desired physical properties and chemical properties. Primary amides form supramolecular heterosynthons, these synthons represent an opportunity for a design of multi-component crystals in which one molecule contains a primary amide and a second molecule which is complimentary to the primary amide, usually carboxylic acids. The progress with regards to the screening process for the determination of co-crystals is evident in the literature, In particular, high throughput solution growth methods and solvent drop grinding. The comparison of Isonicotinamide and Benzamide as a co-crystal component has been presented. This study was motivated by the observation that the CSD contains 24 Isonicotinamide and 1 Benzamide co-crystal. The interaction with carboxylic acids is the focus of the work, in particular those which form Isonicotinamide co-crystal are being screened with Benzamide. Our work utilises a ReactArray Microvate to carry out the low throughput solution growth on a matrix of carboxylic acid with Benzamide, this study has been coupled with the Kofler hot stage microscope method which visually aids to screen and view co-crystal phase formation. Crystallisation screens have resulted in the identification of known co-crystal phases of Isonicotinamide and Benzamide, additionally new co-crystal phases have also been identified with Fumaric, 3-hydroxybenzoic acid, Mandelic Acid, 4-Nitrobenzoic Acid and Tartaric Acid. Single crystal structures of the Fumaric and 4-Nitrobenzoic acid have been obtained. In order to develop an understanding of co-crystal formation in Isonicotinamide and Benzamide with our supramolecular library, packing landscape analysis is being undertaken using both the CSD and crystal structures we have obtained. This is undertaken as collaboration with Dr Andy Parkin and Professor Gilmore (University of Glasgow), we have identified that the dSNAP analysis is a way forward for the analysis of how co-crystals pack. The analysis highlighted the subtleties that were present in the packing motifs of the Isonicotinamide co-crystals. In particular the cis and trans orientation of the amide and acid carbonyl to each other and the planar and off planar layer assemblies. All of which are required to maximise the hydrogen bond usage of the components comprising the co-crystals. Further investigations have led to the collaborative project with Syngenta Ltd in the design of a co-crystal screen using a high through-put robot, Crissy® -Automation Platform by Zinsser Analytical, using an extended screen of 16 acid coformers with Isonicotinamide, Benzamide and Nicotinamide the sample have been characterised using a reflectance diffraction method, GADDS. Further analysis of this data involves the use of polySNAP, which has led to further collaboration with Professor Gilmore¿s group. / Syngenta

Mixed-metal supramolecular complexes containing one or two RuII light absorbing subunits coupled through polyazine bridging ligands to a RhIII reactive metal center were prepared for use as photocatalysts for the production of solar H2 fuel from H2O. The electrochemical, photophysical, and photochemical properties upon variation of the monodentate, labile ligands coordinated to the Rh reactive metal center were investigated. Bimetallic complexes [(Ph2phen)2Ru(dpp)RhX2(Ph2phen)]3+ (Ph2phen = 4,10-diphenyl-1,10-phenanthroline; dpp = 2,3-bis(2-pyridyl)pyrazine; X = Br- or Cl-) were prepared using a building block approach, allowing for selective component choice. The identity of the halide coordinated to Rh did not impact the light absorbing or excited state properties of the structural motif. However, the o-donating ability of the halides modulated the Rh-based cathodic electrochemistry and required the use of multiple pathways to explain the reduction of Rh by two electrons. Regardless of halide identity, the bimetallic complex possessed a Ru-based HOMO (highest occupied molecular orbital) and Rh-based LUMO (lowest unoccupied molecular orbital) important for photoinitiated electron collection at Rh. As a photocatalyst for H2 evolution, the X = Br- complex produced nearly 30% more H2 than the X = Cl- analogue. H2 production experiments with added halide suggested that ion pairing with halides played a major role in catalyst deactivation, which provided evidence for the importance of component selection for photocatalyst design. New trimetallic complex [{(bpy)2Ru(dpp)}2Ru(OH)2](PF6)5 (bpy = 2,2'-bipyridine) was prepared for comparison to halide analogues [{(bpy)2Ru(dpp)}2RhX2](PF6)5 (X = Br- or Cl-). The synthesis of a halide-free supramolecule containing OH- ligands afforded an ideal system to further examine the impact of the ligands at the reactive metal center on H2 photocatalysis. Electrochemistry results revealed that while the identity of the ligands at Rh did modulate the Rh-based reduction potential, all three complexes possessed a Ru-based HOMO and Rh-based LUMO. The light absorbing properties were not impacted by the identity of the monodentate ligands at Rh; however, the excited state properties did vary upon changing the ligands at Rh. The hydroxo trimetallic complex functioned as a photocatalyst for H2 production in organic solvent, producing nearly double the amount of H2 as the highest performing Br-' trimetallic complex in DMF solvent. Interestingly, H2 production studies in high dielectric aqueous solvent revealed no discrepancies in H2 evolution upon variation of the ligands at Rh, which further supported the ion pairing phenomenon realized for the bimetallic motif. Variation of the labile ligands coordinated to the Rh reactive metal center in RuIIRhIII multimetallic supramolecules provided important insight about the large impact of small structural variation on H2 photocatalysis. Electrochemical, photophysical, and photochemical studies of new RuIIRhIII complexes afforded a deeper understanding of the molecular processes important for the design of new complexes applicable to solar fuel production schemes. / Ph. D.

The goal of this research is to test the design constraints of active dpp-bridged RuII,RhIII (dpp = 2,3-bis(2-pyridyl)pyrazine)) supramolecular photocatalysts for water reduction to H2 and provide mechanistic insights into the catalytic cycle. Two member of a new RuII,RhIII motifs with only one Rh-'Cl bond, [(bpy)2Ru(dpp)RhCl(tpy)](PF6)4 ( bpy = 2,2'-bipyridine, tpy = 2,2':6,2"-terpyridine) and [(bpy)2Ru(dpp)RhCl(tpm)](PF6)4, (tpm = tris(1-pyrazolyl)methane), and a cis-RhCl2 model system, [(bpy)2Ru(dpp)RhCl2(bpy)](PF6)3, were prepared. This new motif was to test whether two Rh-'Cl bonds on RhIII are required for the photocatalytic water reduction. 1H NMR spectroscopic analysis of complexes prepared using deuterated ligands was used to characterize these three RuII,RhIII supramolecular complexes. Electrochemical studies suggested that replacing bpy with a tridentate ligand on RhIII shifts the RhIII/II and RhII/I reduction couples positively, which can modulate the orbital energetics of the RhIII LUMO (lowest-unoccupied molecular orbital). This substitute also changes the rate of ligand dissociation following the reduction of RhIII. In tpm and bpy systems, RhII intermediate is more stable than that in the tpy system. All three complexes were good light absorbers in the visible region and weak emitters from their emissive Ru(dπ)-'dpp(π*) 3MLCT (metal-to-ligand charge transfer) excited states at room temperature. The population of a low-lying 3MMCT (metal-to-metal charge transfer) ES (excited state) from the 3MLCT ES contributed to the weak emission, indicating an important intramolecular electron transfer process from dpp' to RhIII upon photoexcitation. The lower-lying 3MMCT excited state in the tpm and tpy systems relative to the bpy system result in a higher rate constant (ket = 2.6 x 10^7 vs 1.7 x 10^7 s-1) for intramolecular electron transfer. Spectrophotochemical analysis suggested that all three complexes were photoinitiated electron collectors capable of collecting two electrons on the RhIII center to generate the RuII,RhI species in the presence of DMA (N,N-dimethylaniline). The observed H2 production from water using [(bpy)2Ru(dpp)RhCl(tpm)](PF6)4 and [(bpy)2Ru(dpp)RhCl(tpy)](PF6)4 established that two halides on RhIII are not necessary in the dpp-bridge RuII,RhIII supramolecular photocatalytic-water-reduction system. This new discovery opens a new approach to the design of different RuII,RhIII motifs for photocatalysis. The active species for water reduction is proposed to be [(bpy)2Ru(dpp)RhICl(TL)]3+ from [(bpy)2Ru(dpp)RhCl(TL)](PF6)4 (TL (terminal ligand) = tpy or tpm) and [(bpy)2Ru(dpp)Rh(bpy)]3+ from [(bpy)2Ru(dpp)RhCl2(bpy)](PF6)3 respectively. Included here is the design and study of a RuII,RhI complex, [(bpy)2Ru(dpp)RhCl(COD)](PF6)3 (COD =1,5-cyclooctadiene) to provide more insights into the photophysical and photochemical properties of polypyridyl RuII,RhI species. Electrochemical and photophysical studies revealed a dpp-based LUMO in this RuII,RhI complex, suggesting dpp reduction upon photoexcitation. Photochemical study found that [(bpy)2Ru(dpp)RhCl(COD)](PF6)3 is an active photocatalyst for water reduction and that additional reduction(s) is (are) required after the generation of the RuII,RhI active species in the RuII,RhIII supramolecular photocatalytic H2 production system. This hypothesis was supported by the electrocatalytic behaviors of the RuII,RhIII supramolecular complexes for proton reduction. Cyclic voltammetry results in the presence of an acid suggested that the protonolysis of the RuII,RhIIH and RuII,RhIH species are electrocatalytic H2-evolution pathways. The mechanism is acid-dependent and influenced by terminal ligand. The studies of electrocatalytic proton reduction on these RuII,RhIII complexes suggested several possible intermediates involved in the photocatalytic water reduction cycle. The insights gained from this research can provide guidance in designing new type of RuII,RhIII and RuII,RhI complexes with better photocatalytic and/or electrocatalytic H2 production performance. / Ph. D.

Beaucoup d'efforts dans le domaine des matériaux polymères sont déployés pour développer de nouveaux matériaux fonctionnels pour des applications spécifiques, souvent très sophistiquées, en employant des méthodes simplifiées de synthèse et de préparation. Cette thèse porte sur les polymères photosensibles – i.e. des matériaux fonctionnels qui répondent de diverses manières à la lumière – qui sont préparés à l'aide de la chimie supramoléculaire – i.e. une méthode de préparation qui repose sur l'auto-assemblage spontané de motifs moléculaires plus simples via des interactions non covalentes pour former le matériau final désiré. Deux types de matériaux photosensibles ont été ciblés, à savoir les élastomères thermoplastiques à base de copolymères à blocs (TPE) et les complexes d'homopolymères photosensibles. Les TPEs sont des matériaux bien connus, et même commercialisés, qui sont généralement composés d’un copolymère tribloc, avec un bloc central très flexible et des blocs terminaux rigides qui présentent une séparation de phase menant à des domaines durs isolés, composés des blocs terminaux rigides, dans une matrice molle formée du bloc central flexible, et ils ont l'avantage d'être recyclable. Pour la première fois, au meilleur de notre connaissance, nous avons préparé ces matériaux avec des propriétés photosensibles, basé sur la complexation supramoléculaire entre un copolymère tribloc simple parent et une petite molécule possédant une fonctionnalité photosensible via un groupe azobenzène. Plus précisément, il s’agit de la complexation ionique entre la forme quaternisée d'un copolymère à blocs, le poly(méthacrylate de diméthylaminoéthyle)-poly(acrylate de n-butyle)-poly(méthacrylate de diméthylaminoéthyle) (PDM-PnBA-PDM), synthétisé par polymérisation radicalaire par transfert d’atomes (ATRP), et l'orange de méthyle (MO), un composé azo disponible commercialement comportant un groupement SO3 -. Le PnBA possède une température de transition vitreuse en dessous de la température ambiante (-46 °C) et les blocs terminaux de PDM complexés avec le MO ont une température de transition vitreuse élevée (140-180 °C, en fonction de la masse molaire). Des tests simples d'élasticité montrent que les copolymères à blocs complexés avec des fractions massiques allant de 20 à 30% présentent un caractère élastomère. Des mesures d’AFM et de TEM (microscopie à force atomique et électronique à ii transmission) de films préparés à l’aide de la méthode de la tournette, montrent une corrélation entre le caractère élastomère et les morphologies où les blocs rigides forment une phase minoritaire dispersée (domaines sphériques ou cylindriques courts). Une phase dure continue (morphologie inversée) est observée pour une fraction massique en blocs rigides d'environ 37%, ce qui est beaucoup plus faible que celle observée pour les copolymères à blocs neutres, dû aux interactions ioniques. La réversibilité de la photoisomérisation a été démontrée pour ces matériaux, à la fois en solution et sous forme de film. La synthèse du copolymère à blocs PDM-PnBA-PDM a ensuite été optimisée en utilisant la technique d'échange d'halogène en ATRP, ainsi qu’en apportant d'autres modifications à la recette de polymérisation. Des produits monodisperses ont été obtenus à la fois pour la macroamorceur et le copolymère à blocs. À partir d'un seul copolymère à blocs parent, une série de copolymères à blocs partiellement/complètement quaternisés et complexés ont été préparés. Des tests préliminaires de traction sur les copolymères à blocs complexés avec le MO ont montré que leur élasticité est corrélée avec la fraction massique du bloc dur, qui peut être ajustée par le degré de quaternisation et de complexation. Finalement, une série de complexes d'homopolymères auto-assemblés à partir du PDM et de trois dérivés azobenzènes portant des groupes (OH, COOH et SO3) capables d'interactions directionnelles avec le groupement amino du PDM ont été préparés, où les dérivés azo sont associés avec le PDM, respectivement, via des interactions hydrogène, des liaisons ioniques combinées à une liaison hydrogène à travers un transfert de proton (acidebase), et des interactions purement ioniques. L'influence de la teneur en azo et du type de liaison sur la facilité d’inscription des réseaux de diffraction (SRG) a été étudiée. L’efficacité de diffraction des SRGs et la profondeur des réseaux inscrits à partir de films préparés à la méthode de la tournette montrent que la liaison ionique et une teneur élevée en azo conduit à une formation plus efficace des SRGs. / Much effort in the area of polymer materials involves the development of new functional materials for specific, often highly sophisticated, applications using simplified methods of synthesis and preparation. This thesis focuses on photo-responsive polymers – i.e. functional materials that respond in various ways to light – that are prepared with the aid of supramolecular chemistry – i.e. a preparation method that relies on the spontaneous selfassembly of simpler molecular building blocks via noncovalent interactions to form the final targeted material. Two types of photo-responsive materials were targeted, namely block copolymer thermoplastic elastomers (TPEs) and photo-responsive homopolymer complexes. TPEs are well-known, even commercial, materials that are typically based on triblock copolymers with a highly flexible middle block and rigid outer blocks that phase separate into isolated domains of the hard, outer block phase within a matrix of the soft block phase, and they have the advantage of being recyclable. For the first time, to our knowledge, we have prepared such materials with photo-responsive properties based on supramolecular complexation between a simpler parent triblock copolymer and a small molecule possessing the photo-responsive functionality via an azobenzene group. Specifically, this involved the ionic complexation of the quaternized form of a block copolymer, poly(dimethylaminoethyl methacrylate)-poly(n-butyl acrylate)-poly(dimethylaminoethyl methacrylate) (PDM-PnBAPDM), synthesized by atom transfer radical polymerization (ATRP), with methyl orange (MO), a commercially available SO3 --functionalized azo-containing compound. PnBA has a subambient glass transition (-46 °C) and the MO-complexed PDM outer blocks have a high glass transition (140-180 °C, depending on the molecular weight). Simple elasticity tests show that the complexed block copolymers with hard block weight fractions between about 20 and 30% have elastomeric character. AFM and TEM (atomic force and transmission electron microscopies) of spin-coated films show a correlation between the elastomeric character and morphologies where the hard block forms a dispersed minority phase (spherical and/or short cylindrical domains). A continuous hard phase (inverted morphology) is observed for a hard block content of around 37 wt %, which is much lower than found for neutral block iv copolymers due to ionic interactions. Reversible photoisomerization was demonstrated for these materials in both solution and in film form. The synthesis of the PDM-PnBA-PDM block copolymer was then optimized by using the halogen exchange technique in ATRP, along with other modifications to the polymerization recipe. Monodisperse products were obtained for both the macroiniaitor and the block copolymer. Based on a single parent block copolymer, a series of partially/fully quaternized and complexed block copolymers were prepared. Preliminary stretching tests on the MO-complexed block copolymers showed that their elasticity is correlated with the hard block content, which can be tuned by the degree of quaternization and complexation. Finally, a series of homopolymer complexes self-assembled from PDM and azobenzene derivatives bearing three different groups capable of directed interactions with the amino moiety of PDM (OH, COOH and SO3 -) were prepared, where the azo derivative associates with PDM via hydrogen-bonding interactions, by ionic bonding mixed with hydrogen bonding through proton-transfer (acid-base) interactions, and by purely ionic interactions via ion exchange procedures, respectively. The influence of the azo content and bonding type on surface relief grating (SRG) inscription was investigated. The SRG diffraction efficiencies and grating depths in spin-coated films show that ionic bonding and high azo content leads to more efficient SRG formation.