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Exploring the crystal energy landscapes of porous molecular crystalsPyzer-Knapp, Edward Oliver January 2014 (has links)
No description available.
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Asymmetrically substituted donor-acceptor heterocycles for molecular electronicsAtkins, Karen Jane January 1990 (has links)
No description available.
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Synthesis and characterisation of novel functional phthalocyanine nano-porous materialsBurt, Luke Anthony January 2018 (has links)
This project was focused on the synthesis of novel phthalocyanines for the construction of porous molecular crystals that incorporate the desirable properties associated with phthalocyanine complexes. Conventional phthalocyanines are relatively insoluble, therefore, remain difficult to process, characterise and effectively crystallise. To counteract this problem, bulky 2,6-di-iso-propylphenoxy substituents were placed around the aromatic core of the phthalocyanine macrocycle and proved to successfully inhibit the co-facial aggregation which limits their solubility. These bulky groups also direct the crystallisation of the phthalocyanine macrocycle inducing a cubic packing arrangement with significant accessible solvent filled voids. The aim of this work was the modification of this 2,6-di-isopropylphenoxy substituted phthalocyanine to enhance the magnetic and catalytic properties and demonstrate its suitability as a platform for creating iso-reticular systems with increased functionality. It was anticipated that mixed double decker complexes of this derivative and another phthalocyanine macrocycle would form crystals with the same cubic spatial arrangement, while maintaining their high catalytic activity or single molecular magnetism behaviour. Firstly, a larger number of transition metals along with some lanthanide metals have been incorporated within this substituted phthalocyanine, extending the previous work on this system. Furthermore, the corresponding contracted macrocycle boron subphthalocyanine was also investigated. While the 2,6-diisopropylphenyl substituents did not greatly affect the electronic properties of the subphthalocyanine, the solid state properties of the material proved interesting. The lanthanide phthalocyanine complexes were further employed in the preparation of lanthanide double decker phthalocyanines that possess single molecule magnetic properties. While retaining this desired property, they also crystallised to produce clathrates with large solvent filled voids. A different double decker complex which contained two iron metal centres bridged by a single nitrogen atom was also prepared from the octa substituted 2,6-di-iso-propylphenoxy phthalocyanine and an unsubstituted phthalocyanine. This nitrido bridged di-iron phthalocyanine complex displayed similar catalytic activity to previously reported systems of this kind and crystallised to afford cubic crystals with large solvent filled voids. These were shown to be accessible by both solvent and ligand exchange. Suitable bidentate ligands for structural stabilisation could be also incorporated. Finally, the preparation of an alternatively substituted phthalocyanine for the construction of a potential porous molecular crystal was studied. By synthesising a hexamethylindan substituted phthalonitrile, it was possible to obtain a soluble phthalocyanine that crystallised to give a clathrate that contained large one-dimensional voids.
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Transition metal complexes of functionalized isocyanides as building blocks for molecular solid state materials劉嘉賢, Lau, Ka-yin. January 1997 (has links)
published_or_final_version / Chemistry / Master / Master of Philosophy
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Studies of exciton interactions in molecular aggregatesGianneschi, Leon Paul January 1977 (has links)
211 leaves : ill., tables, graphs ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.1978) from the Deaprtment of Physical and Inorganic Chemistry, University of Adelaide
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Studies of exciton interactions in molecular aggregates.Gianneschi, Leon Paul. January 1977 (has links) (PDF)
Thesis (Ph.D. 1978) from the Deaprtment of Physical and Inorganic Chemistry, University of Adelaide.
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Studies in the luminescence of organic molecular crystals.Riceman, William David. January 1970 (has links) (PDF)
Thesis (M.Sc.)--University of Adelaide, Dept. of Physics, 1971.
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Transition metal complexes of functionalized isocyanides as building blocks for molecular solid state materials /Lau, Ka-yin. January 1997 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1997. / Includes bibliographical references.
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NMR investigations of dynamic phenomena in crystalline organic solidsCameron, Kenneth Stuart January 1997 (has links)
The study of the following compounds is based on the premise that high symmetry in molecules should lead to low barriers to molecular motion even in the solid state i.e. the principle of least distress. The study of 3,3-diethylpentane is a very nice example of a phase change which results in no chemical shift changes but, produces a sharp discontinuity in the rate of ethyl group rotation. A large discontinuity in rate of molecular motion is also observed in 4,4-dipropylheptane which is also due to a phase change. The following study of tetraalkyl ammonium halides revealed both alkyl group rotation and cation tumbling to be occurring. This is most significant in the tetramethyl ammonium halides where the effects of methyl rotation and cation tumbling are shown to overlap considerably. The activation energies for the cation tumbling in the tetramethyl ammonium halides are Ea= 30 - 36 kJ mol−1 and for ethyl group rotation in tetraethyl ammonium chloride are, △H†; = 57.8 kJ mol−1 and △S†; = 45.9 J K−1 mol−1. The chemical shift differences in each chain due to different chain lengths is seen in tetrabutyl ammonium iodate which also shows a sudden coalescence and introduction of rapid molecular motion after two small phase changes. This compound has a large phase change which also affects the rate of molecular motion. The tetraalkyl phosphonium halides have a greater degree of molecular motion than the ammoniums in the temperature range studied and also offer the chance to use Tip measurements. The tetramethyl phosphonium halides show a distinct cation tumbling as opposed to the ammoniums. The process in the chloride and bromide which have hexagonal structures gives △H†; ~ 30 kJ mol−1 and negative △S†; values and the lower symmetry iodide has △H†; = 45.2 kJ mol−1 and a positive value of △S†;. The tetraethyl phosphonium halides show ethyl group rotations measurable to varying degrees by 13CT1p. The tetrabutyl phosphonium halides also have the different chain lengths as seen for the ammonium compounds. They also show bond rotations which are quite difficult to measure by 13CT1p values. The study of bis-(hydroxymethyl)cyclopentane (BHMCP) in an attempt to study ring puckering/pseudorotation in cyclopentane derivatives in the solid state reveals a hydrogen bond exchange process (△Gc†;~ 60 kJ mol−1). The bicyclic derivatives of BHMCP showed no such molecular motions but did reveal some interesting solid- solid phase transitions and chemical shift changes. The study of trans-cyclopentanediol yields △H†; = 77.0 and △S&†; = 184 J K−1 mol−1 for the processes involved. The study of 4,4-dimethyl-trans−1,2-cyclopentanediol reveals two processes. One results in the coalescence of resonances and appears to be a hydrogen bonding exchange process. The other is a much lower energy process (Ea ~ 26 kJ mol−1) which could be a ring puckering process. The study of sulpholane also shows significant molecular motion with △H&†; = 50.6 kJ mol−1 and △S&†; = 77.9 J K−1 mol−1.
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The structure determination of BICYL10 [2,2,2] octyl-2 P-bromobenzenesulfonate in the solid phaseMueller, Patricia Westbrook 05 1900 (has links)
No description available.
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