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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Transmission of polar effects : Studies in diphenylacetylenes, diphenylethylenes and phenylnaphthalenes

Ghadir, K. D. F. January 1986 (has links)
No description available.
2

Sustainable Fault-handling Of Reconfigurable Logic Using Throughput-driven Assessment

Sharma, Carthik 01 January 2008 (has links)
A sustainable Evolvable Hardware (EH) system is developed for SRAM-based reconfigurable Field Programmable Gate Arrays (FPGAs) using outlier detection and group testing-based assessment principles. The fault diagnosis methods presented herein leverage throughput-driven, relative fitness assessment to maintain resource viability autonomously. Group testing-based techniques are developed for adaptive input-driven fault isolation in FPGAs, without the need for exhaustive testing or coding-based evaluation. The techniques maintain the device operational, and when possible generate validated outputs throughout the repair process. Adaptive fault isolation methods based on discrepancy-enabled pair-wise comparisons are developed. By observing the discrepancy characteristics of multiple Concurrent Error Detection (CED) configurations, a method for robust detection of faults is developed based on pairwise parallel evaluation using Discrepancy Mirror logic. The results from the analytical FPGA model are demonstrated via a self-healing, self-organizing evolvable hardware system. Reconfigurability of the SRAM-based FPGA is leveraged to identify logic resource faults which are successively excluded by group testing using alternate device configurations. This simplifies the system architect's role to definition of functionality using a high-level Hardware Description Language (HDL) and system-level performance versus availability operating point. System availability, throughput, and mean time to isolate faults are monitored and maintained using an Observer-Controller model. Results are demonstrated using a Data Encryption Standard (DES) core that occupies approximately 305 FPGA slices on a Xilinx Virtex-II Pro FPGA. With a single simulated stuck-at-fault, the system identifies a completely validated replacement configuration within three to five positive tests. The approach demonstrates a readily-implemented yet robust organic hardware application framework featuring a high degree of autonomous self-control.
3

Innovation och kreativitet i en hierarkisk miljö – Malmö högskola - Medieteknik

Sobczyk, Inez January 2010 (has links)
Medieteknik är en avdelning på Malmö högskola som dagligen handskas med att vara en innovativ och utvecklande del i en större organisation. Något som skapar möjligheter, men även begränsningar. Högskolans krav, resulterar tillsammans med omvärldens föränderlighet i att avdelningen måste växla mellan struktur, planering, genomförande – och – utveckling, innovation av innehåll, utbud, pedagogik.Syftet med rapporten är att undersöka hur en innovativ och kreativ utvecklingsmiljö skapas och bevaras i en organisation/myndighet. Genom en enkätundersökning skapas det empiriska material som, tillsammans med studiet av högskolans villkor, samt förankring i den teoretiska referensramen besvarar den aktuella frågeställningen: Vilka förutsättningar kan påverka en avdelning att arbeta och agera innovativt inom ramen för den större organisationens styrning och krav?Slutsatsen är att Malmö högskola ställs inför en rad motstridiga krav som kräver jämvikt inom organisationen, för att arbetet på avdelningsnivå ska fungera. Detta då den stora organisationen skapar förutsättningar för medieteknik, som i dagsläget inte når hela vägen fram, och det existerar ett glapp som verkar hämmande inom en rad olika områden. Det krävs bland annat bättresamhörighet mellan medieteknik och den övergripande organisationen. Högskolan uppmuntras även att skapa tydligare riktlinjer för dess anställda, samt ge bättre stöd för växelverkan mellan deidentifierade kraven på struktur och innovation. Utveckling av forskningsverksamheten, samt avdelningens inblandning i denna rekommenderas, likaså strategisk diskussion. / Medieteknik is a department at Malmo University that on a daily basis struggles with being an innovative and developing part of a bigger organization. This creates possibilities, as well as limitations. The universities demands, together with the ever-changing world, forces the department to vary between structure, planning, implementation – and – development, innovation of content, range and pedagogy.The purpose of this essay is to examine how to create an innovative and creative environmental development within an organization/public authority. The use of a questionnaire creates the essays empirical material, which, together with the study of the universities conditions, as well as with the support of the theoretical reference, answers the question at issue: Which conditions can affect a department to work and act in an innovative way, within the boundaries of the bigger organizationsrule and demands?The conclusion is that Malmo University is constantly faced with a number of contradictory demands that require balance within the organisation, so that work on department level is to function efficiently. This because the bigger organization creates conditions for medieteknik, which currently do not function in an effective way, and hence create a weak link within different fields.Amongst other things there should exist better participation between the department and Malmo University, as well as more specific guidelines for the employees. Better support for the interactionbetween the identified demands of structure and innovation should be given. The development of research would benefit of the departments involvement, and is a recommendation, alongside with strategic discussion.
4

Estudo atomístico da desordem eletrônica em filmes amorfos de polímeros conjugados / Atomistic Study of Electronic Disorder on Amorphous Films of Conjugated Polymers

Silva, Rodrigo Ramos da 10 October 2014 (has links)
O emprego de polímeros conjugados e blendas como camada ativa de diodos emissores de luz ou células fotovoltaicas é foco de intenso desenvolvimento científico na atualidade. O desempenho eletro-ótico de tais dispositivos é fortemente dependente das características estruturais e eletrônicas dos componentes poliméricos ou moleculares, que são difíceis de serem quantificadas, demandando a integração de resultados experimentais e modelagem teórica. A desordem intrínseca desses materiais também dificulta a modelagem e a simulação, sendo necessário o emprego de diferentes e complementares métodos e técnicas de física computacional. O presente trabalho tem como objetivo o estudo, em nível atomístico, da correlação entre propriedades morfológicas e eletrônicas de filmes poliméricos com alta desordem de: I) poli-para-fenileno-vinileno (PPV); II) poli-3-hexil-tiofeno (P3HT) e sua blenda com fulereno (C60). Empregamos modelagem por Dinâmica Molecular Clássica dos sistemas desordenados em temperatura finita; implementamos para tal adaptações específicas no Campo de Forças Universal, baseadas em cálculos quânticos de primeiros princípios. Para obtermos a estrutura eletrônica de modelos selecionados utilizamos método de Hartree-Fock semiempírico. O sistema de PPV é estudado com respeito à variação das propriedades morfológicas ao longo do processo de deformação uniaxial. Estabelecemos correspondência entre os efeitos do estiramento e o surgimento de anisotropia no espectro de fotoluminescência observado experimentalmente. Para os sistemas de P3HT simulamos diferentes tipos de empacotamento, estudamos as propriedades morfológicas e calculamos os estados eletrônicos relevantes ao transporte de buracos pelo polímero. Vemos como majoritária a ocorrência de estados com comprimento conjugado de quatro e cinco meros; além disso, com a desordem estrutural os níveis eletrônicos localizados passam a exibir grande proximidade em energia, com pouca relação ao comprimento de conjugação. Isso resulta no surgimento de uma Densidade de Estados gaussiana com largura de aproximadamente 100meV que se mostra independente das diferenças morfológicas entre os modelos simulados. / The use of organic conjugated polymers and blends as active layers of light emitting diodes and photovoltaic cells has been the focus of intense scientific development in recent years. The electro-optical performance of such devices depends strongly on the structural and electronic properties of the polymeric or molecular components, and is of difficult characterization, demanding integration of experimental results and theoretical modeling. A complicating factor to the theoretical modeling is the intrinsic disorder in these materials, which demands the use of different and complementary techniques and methods of computational physics. The goal of the present work is to study at the atomistic level the correlation between morphological and electronic properties of highly disordered films of: I) poly-para-phenylene-vinylene (PPV); II) poly-3-hexyl-thiophene (P3HT) and blends with fullerenes (C60). We applied Classical Molecular Dynamics to model the disordered systems at finite temperature employing the well-known Universal Force Field, to which we implemented specific corrections based on first-principles quantum calculations. For selected models we calculated the electronic structure through semiempirical Hartree-Fock. The PPV system was studied focusing on the effect of uniaxial stretching on morphological properties. We have established a connection between morphology effects and the anisotropy of light emission detected experimentally. For P3HT systems we simulated different packing systems and studied morphological properties, and the electronic structure of the localized states relevant to hole transport in the polymer film. We found higher occurrence of 4- and 5-mer long conjugated electronic states. Moreover, the structural disorder affects the electronic levels, reducing the energy separation of conjugated segments of different lengths. This makes possible the occurrence of a gaussian Density of States of approximately 100meV width, regardless of the different morphological signatures of the different simulated models.
5

Estudo atomístico da desordem eletrônica em filmes amorfos de polímeros conjugados / Atomistic Study of Electronic Disorder on Amorphous Films of Conjugated Polymers

Rodrigo Ramos da Silva 10 October 2014 (has links)
O emprego de polímeros conjugados e blendas como camada ativa de diodos emissores de luz ou células fotovoltaicas é foco de intenso desenvolvimento científico na atualidade. O desempenho eletro-ótico de tais dispositivos é fortemente dependente das características estruturais e eletrônicas dos componentes poliméricos ou moleculares, que são difíceis de serem quantificadas, demandando a integração de resultados experimentais e modelagem teórica. A desordem intrínseca desses materiais também dificulta a modelagem e a simulação, sendo necessário o emprego de diferentes e complementares métodos e técnicas de física computacional. O presente trabalho tem como objetivo o estudo, em nível atomístico, da correlação entre propriedades morfológicas e eletrônicas de filmes poliméricos com alta desordem de: I) poli-para-fenileno-vinileno (PPV); II) poli-3-hexil-tiofeno (P3HT) e sua blenda com fulereno (C60). Empregamos modelagem por Dinâmica Molecular Clássica dos sistemas desordenados em temperatura finita; implementamos para tal adaptações específicas no Campo de Forças Universal, baseadas em cálculos quânticos de primeiros princípios. Para obtermos a estrutura eletrônica de modelos selecionados utilizamos método de Hartree-Fock semiempírico. O sistema de PPV é estudado com respeito à variação das propriedades morfológicas ao longo do processo de deformação uniaxial. Estabelecemos correspondência entre os efeitos do estiramento e o surgimento de anisotropia no espectro de fotoluminescência observado experimentalmente. Para os sistemas de P3HT simulamos diferentes tipos de empacotamento, estudamos as propriedades morfológicas e calculamos os estados eletrônicos relevantes ao transporte de buracos pelo polímero. Vemos como majoritária a ocorrência de estados com comprimento conjugado de quatro e cinco meros; além disso, com a desordem estrutural os níveis eletrônicos localizados passam a exibir grande proximidade em energia, com pouca relação ao comprimento de conjugação. Isso resulta no surgimento de uma Densidade de Estados gaussiana com largura de aproximadamente 100meV que se mostra independente das diferenças morfológicas entre os modelos simulados. / The use of organic conjugated polymers and blends as active layers of light emitting diodes and photovoltaic cells has been the focus of intense scientific development in recent years. The electro-optical performance of such devices depends strongly on the structural and electronic properties of the polymeric or molecular components, and is of difficult characterization, demanding integration of experimental results and theoretical modeling. A complicating factor to the theoretical modeling is the intrinsic disorder in these materials, which demands the use of different and complementary techniques and methods of computational physics. The goal of the present work is to study at the atomistic level the correlation between morphological and electronic properties of highly disordered films of: I) poly-para-phenylene-vinylene (PPV); II) poly-3-hexyl-thiophene (P3HT) and blends with fullerenes (C60). We applied Classical Molecular Dynamics to model the disordered systems at finite temperature employing the well-known Universal Force Field, to which we implemented specific corrections based on first-principles quantum calculations. For selected models we calculated the electronic structure through semiempirical Hartree-Fock. The PPV system was studied focusing on the effect of uniaxial stretching on morphological properties. We have established a connection between morphology effects and the anisotropy of light emission detected experimentally. For P3HT systems we simulated different packing systems and studied morphological properties, and the electronic structure of the localized states relevant to hole transport in the polymer film. We found higher occurrence of 4- and 5-mer long conjugated electronic states. Moreover, the structural disorder affects the electronic levels, reducing the energy separation of conjugated segments of different lengths. This makes possible the occurrence of a gaussian Density of States of approximately 100meV width, regardless of the different morphological signatures of the different simulated models.
6

Energy level alignment mechanisms at inorganic-organic semiconductor interfaces investigated with photoelectron spectroscopy

Schultz, Thorsten 08 January 2019 (has links)
Hybride anorganische/organische Systeme (HIOS) sind von großem Interesse für Grundlagenforschung und neue (opto)-elektronische Bauteile. Um effiziente Bauteile zu entwickeln, ist ein Verständnis der Energielevelanordnung (ELA) an der Grenzfläche von entscheidender Bedeutung. Es wird demonstriert, wie Oberflächen mit heterogener Austrittsarbeit die Resultate von ultravioletter Photoelektronenspektroskopie (UPS) beeinflussen. Durch den Vergleich experimenteller Daten mit Berechnungen zeigt sich, dass das lokale elektrostatische Potential oberhalb der Oberfläche zur Ausbildung einer zusätzlichen Energiebarriere für Elektronen über Bereichen mit niedriger Austrittsarbeit führt, was die gemessene Sekundärelektronenkante zu höheren kinetischen Energien verschiebt. Der Einfluss von Streifengröße und experimentellen Parametern wird theoretisch und experimentell gezeigt. Im zweiten Teil dieser Arbeit wird gezeigt, wie man dünne organische Donator/Akzeptor Zwischenschichten nutzen kann, um die ELA zwischen typischen anorganischen und organischen Halbleitern zu kontrollieren. Die Austrittsarbeit von anorganischen Substraten lässt sich so zwischen 2.2-6.0 eV variieren. Der Einfluss von Zuständen in der Bandlücke des anorganischen Halbleiters auf die Bandverbiegung wird im Detail untersucht und es wird ein Model vorgeschlagen, welches das Pinning des Fermi-Niveaus an diesen Zuständen beschreibt. Es wird experimentell gezeigt, dass die Dotierung des anorganischen Halbleiters kaum Einfluss auf die ELA hat. Weiterhin wird die ELA zwischen dem Übergangsmetall-Dichalcogenid WSe2 und dem organischen Akzeptor C60F48 untersucht. Mit Hilfe von STM und STS Messungen wurde gezeigt, dass C60F48 geschlossene Domänen auf WSe2 bei Bedeckung mit Submonolagen bildet und dass sich die Energielevel von WSe2 drastisch ändern. Durch Auswerten der Potentialänderung als Funktion des Abstandes von einer C60F48 Kante im STS konnte die Thomas-Fermi-Abschirmlänge von WSe2 auf etwa 2 nm bestimmt werden. / Hybrid inorganic/organic systems (HIOS) have attracted a lot of interest for fundamental studies and novel (opto)-electronic devices during the past decade. For developing efficient devices, an understanding and control of the energy level alignment (ELA) at the hybrid interface is of paramount importance. Firstly, it is demonstrated how surfaces with non-uniform local work function influence the measurement results obtained by ultraviolet photoelectron spectroscopy (UPS). By comparing the measured results with calculations, it is found that the electrostatic potential above the surface leads to an additional energy barrier for electrons above low work function areas, shifting the secondary electron cut-off (SECO) to higher kinetic energies in UPS (averaging effect). The influence of pattern size and measurement conditions on the SECO is shown theoretically and experimentally. In the second part it is shown how thin organic donor/acceptor interlayers can be employed to manipulate the ELA between prototypical inorganic and organic semiconductors. The work function of the inorganic substrate can be tuned between 2.2-6.0 eV. The influence of gap states within the inorganic band gap on the band bending change is investigated in detail and a model is proposed, which describes the pinning of the inorganic energy levels as a function of surface state density. It is further shown experimentally that the bulk doping concentration of the inorganic semiconductor has only little effect on the energetic alignment. Finally, the ELA of the transition metal dichalcogenide monolayer WSe2 with the organic acceptor molecule C60F48 is investigated. Using STM and STS measurements, it is revealed that the C60F48 forms domains on WSe2 in the sub-monolayer regime. By evaluating the potential change as a function of distance from a C60F48 edge in STS, it is possible to derive a value for the Thomas-Fermi screening length of WSe2 of about 2 nm.
7

A Missiological perspective on a South African Chinese House Church in the light of Alan Hirsch's six elements of "Apostolic Genius"

Grant, Stephen Robert January 2013 (has links)
China is a world force. Not only is China seen in the daily news but it has produced the largest church in the world. The church is 100 million people strong (Hattaway 2003:13). Since 1978, modern China has begun to populate the world community with her immigrants. Vast Diaspora communities have been created. The church in China shows all the signs of a Jesus People movement. In 1949 the communist came into power. They ordered all Christian missionaries to leave the country (Aikman 2003:44). By 1953 the last missionary had left (Thompson 1978:186). Mao closed the churches, confiscated property, burned books and bibles and had leaders sent to re-education camps. A time of persecution had begun. Rather than destroy the church, this made it stronger. The church grew from 750,000 to 100 million today. Can this Jesus People movement be experienced in the Diaspora community in South Africa? To evaluate this we use Allan Hirsch’s “The Forgotten Ways” (2006). In this he speaks of Apostolic Genius and the six elements that compose it. Thos elements are Jesus is Lord, Making Disciples, Missional-Incarnational Impulse, Apostolic Environment, Organic Systems and Communitas. These six elements are found expressed within a Jesus people movement. When they are all fully involved, a Jesus People movement is underway. There are 14 Chinese Christian churches in South Africa. The Chinese Diaspora community is 300-350,000 people. The Chinese mostly come from the Fujian province in China. Seventy percent are entrepreneurs and businessmen running shops selling Chinese goods. The researcher has found that the leadership of the churches is from Taiwan. Bringing everything together, the researcher finds the churches are growing at a moderate rate. The expected explosive growth of the church in China is not found in South Africa. The elements of Apostolic Genius are present but only partially expressed. There continues to be potential for the Chinese House church movement to field workers in South Africa. There has been some expressed interest. The Back To Jerusalem Movement is putting missionaries all over the Middle East (Hattaway 2003). It is the opinion of the researcher that putting workers in the Diaspora communities would be a natural extension of that that effort. / Dissertation (MA Theol)--University of Pretoria, 2013. / gm2014 / Science of Religion and Missiology / unrestricted
8

Energy and Charge Transfer at Hybrid Interfaces Probed by Optical Spectroscopy

Mutz, Niklas 30 April 2021 (has links)
Hybride anorganisch/organischen Systeme können die individuellen Vorteile, etwa eine hohe elektronische Mobilität in anorganischen und starke Licht-Materie-Wechselwirkung in organischen Halbleitern, kombinieren. Ein sinnvoller Nutzen dieser Heterostrukturen benötigt ein umfassendes Verständnis der Grenzfläche. Zwei Grenzflächenprozesse werden in dieser Arbeit behandelt. Förster-Resonanzenergietransfer (FRET) wird zwischen einem InGaN/GaN Quantengraben und dem Polymer Cn-ether PPV untersucht. Trotz des hohen internen elektrischen Feldes im Quantengraben, ist effizienter Energietransfer möglich, solange andere nicht-strahlende Zerfallsprozesse unterdrückt werden. Dies wird mittels temperaturabhängiger PL und PLE Spektroskopie gezeigt. PLE demonstriert eine eindeutige Erhöhung der Emission des Akzeptors. Bei höheren Temperaturen dominieren nicht-strahlende Zerfallskanäle. Ladungstransfer wird zwischen MoS2 und dem Molekül H2Pc untersucht. Die Kombination mit organischen Molekülen kann die Funktionalität von MoS2 erweitern. Photoelektronenspektroskopie (PES) zeigt einen Typ-II Heteroübergang an der MoS2/H2Pc Grenzfläche. Angeregte Elektronen gehen von den H2Pc Molekülen in die MoS2 Monolage über, wie mittels einer Verkürzung der PL Lebenszeit von H2Pc gezeigt wird. Photostrommessungen demonstrieren zudem, dass die transferierten Elektronen zu einer erhöhten Photoleitfähigkeit beitragen. Zusätzlich werden auch einzelne 2D Übergangsmetall Dichalkogenide (TMDCs) untersucht. Um TMDCs von hoher Qualität herzustellen, wurde intern eine Wachstumsmethode entwickelt. Mittels PL Spektroskopie werden die so hergestellten Schichten charakterisiert. Die Vielseitigkeit der Methode wird anhand des Wachstums von Mischkristallen und Heterostrukturen gezeigt. Der Einfluss der dielektrischen Funktion des Substrates wird erforscht. Durch die Kombination von PES und Reflexionsmessungen kann eine gleichzeitige Abnahme sowohl der Bandlücke als auch der Exzitonen Bindungsenergie gezeigt werden. / Hybrid inorganic/organic systems can combine the advantages of both materials such as high carrier mobilities in inorganic semiconductors and large light-matter interaction in organic ones. In order to benefit from these heterostructures, a thorough understanding of the interface is needed. Two processes occurring at the interface are looked at in this thesis. Förster resonance energy transfer (FRET) is studied between a single InGaN/GaN quantum well and the polymer Cn-ether PPV. Despite the large internal electric fields in the quantum well, efficient FRET is possible as long as other non-radiative decay channels are suppressed. This is shown by temperature dependent PL and PLE spectroscopy. PLE spectra clearly demonstrate an enhanced light emission from the acceptor. At elevated temperatures, non-radiative decay pathways become dominant. Excited-state charge transfer is studied on MoS2 in combination with the molecule H2Pc. The combination with molecules can extend the functionality of MoS2. Photoelectron spectroscopy (PES) reveals a type II energy level alignment at the MoS2/H2Pc interface. Excited electrons are transferred from H2Pc to MoS2, deduced from a shortening of the H2Pc PL decay time. Photocurrent spectra further show that the transferred electrons contribute to an enhanced photoconductivity. Additionally, bare 2D transition-metal dichalcogenides (TMDCs) are studied. In order to fabricate high-quality TMDC monolayers, a growth method was developed in-house. The grown monolayers are characterised by optical spectroscopy. The versatility of the method is demonstrated by the growth of alloys and heterostructures. The influence of the substrate dielectric function is investigated by comparing band-gaps measured by PES with the exciton transition energies obtained by reflectance measurements. An almost equal reduction in both energies with the substrate dielectric constant is seen.
9

Directing the assembly of multicomponent organic crystals : synthesis, characterisation and structural analysis of multicomponent organic systems formed from dynamic processes

Alomar, Taghrid Saad January 2014 (has links)
Directed assembly of molecular solids continues to attract widespread interest with its fundamental application in a wide range of commercial settings where control of the crystalline state of materials corresponds with product performance. These arenas include pharmaceuticals, personal care formulations, foods, paints and pigments and explosives. In recent times, the assembly of multicomponent organic systems has achieved considerable impetus with the widespread interest in co-crystal systems. However, cogent assembly (or engineering) of multicomponent materials is still in its infancy. Considerable advances in crystal design have been made through consideration of intermolecular ‘synthons’ – identifiable motifs utilising hydrogen bonds – but the translation of other molecular information (conformation, chirality, etc.) into solid state properties (e.g. long-range (translational) symmetry, crystal chirality) remains poorly understood. In this study, we have attempted to evaluate the influence of a chiral centre adjacent to molecular synthons to identify potential translation of information into the solid form. We have compared the co-crystallisation of nicotinamide with both the racemic mixture of malic acid against that with an enantiomerically pure form of the acid (L-malic acid). As well as DL-phenyllactic acid and L-phenyllactic acid. iii It is apparent that recognition between enantiomeric molecular forms play a significant role in the assembly of these systems. This mechanism can be considered independently from the H-bonding networks supporting the hetero-molecular interactions (e.g. acid-amide recognition). Discrimination and control of such interactions may play a role in transmitting chiral molecular information into solid state multi-component assemblies. In order to develop an understanding of co-crystal formation in chiral and achiral forms with intermolecular interactions, the CSD and crystal structures were obtained to do the analysis of how co-crystals pack. This study has also investigated the use of boronic acids. The aim of this study was to investigate the modification of the hydrogen bonding environment within the hydrogen bonded multi-component systems of boroxines. The study also attempted to determine how the starting materials drive the systems between the boronic acid co-crystal and the boroxine adduct.
10

Directing the Assembly of Multicomponent Organic Crystals. Synthesis, characterisation and structural analysis of multicomponent organic systems formed from dynamic processes.

Alomar, Taghrid S. January 2014 (has links)
Directed assembly of molecular solids continues to attract widespread interest with its fundamental application in a wide range of commercial settings where control of the crystalline state of materials corresponds with product performance. These arenas include pharmaceuticals, personal care formulations, foods, paints and pigments and explosives. In recent times, the assembly of multicomponent organic systems has achieved considerable impetus with the widespread interest in co-crystal systems. However, cogent assembly (or engineering) of multicomponent materials is still in its infancy. Considerable advances in crystal design have been made through consideration of intermolecular ‘synthons’ – identifiable motifs utilising hydrogen bonds – but the translation of other molecular information (conformation, chirality, etc.) into solid state properties (e.g. long-range (translational) symmetry, crystal chirality) remains poorly understood. In this study, we have attempted to evaluate the influence of a chiral centre adjacent to molecular synthons to identify potential translation of information into the solid form. We have compared the co-crystallisation of nicotinamide with both the racemic mixture of malic acid against that with an enantiomerically pure form of the acid (L-malic acid). As well as DL-phenyllactic acid and L-phenyllactic acid. iii It is apparent that recognition between enantiomeric molecular forms play a significant role in the assembly of these systems. This mechanism can be considered independently from the H-bonding networks supporting the hetero-molecular interactions (e.g. acid-amide recognition). Discrimination and control of such interactions may play a role in transmitting chiral molecular information into solid state multi-component assemblies. In order to develop an understanding of co-crystal formation in chiral and achiral forms with intermolecular interactions, the CSD and crystal structures were obtained to do the analysis of how co-crystals pack. This study has also investigated the use of boronic acids. The aim of this study was to investigate the modification of the hydrogen bonding environment within the hydrogen bonded multi-component systems of boroxines. The study also attempted to determine how the starting materials drive the systems between the boronic acid co-crystal and the boroxine adduct.

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