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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.
41

Physical characterisation of polymer:fullerene blends for organic photovoltaic devices

Hopkinson, Paul Edward January 2012 (has links)
No description available.
42

Synthese, Kristallstruktur und Bindungseigenschaften von Fulleriden und Fullerensolvaten

Brumm, Holger. January 2002 (has links)
Stuttgart, Univ., Diss., 2002.
43

Ultraschnelle zeitaufgelöste Pump-Probe-Photoelektronenspektroskopie an isolierten und massenselektierten Anionen

Ehrler, Oli T. January 2006 (has links)
Zugl.: Karlsruhe, Universiẗat, Diss., 2006.
44

Simulation der Nanostrukturbildung in Alkali-dotierten Fullerenschichten

Touzik, Andrei. Unknown Date (has links) (PDF)
Techn. Universiẗat, Diss., 2004--Dresden.
45

Photoionization of Fullerens and Atoms Confined in Fullerenes

Hadigheh Javani, Mohammad 18 December 2014 (has links)
The photoionization cross sections of small fullerenes (C28, C32, C40, C44, and C50), and the outer and near-outer shells of atoms (noble gases, alkaline earth) confined endohedrally inside a C60 molecule are calculated employing a time-dependent local density approximation formulation. Plasmon and confinement resonances are found to be a general feature of these cross sections, and dramatic interchannel coupling effects, significantly increasing the atomic cross sections, are exhibited in all cases in the vicinity of the C60 plasmons. Hybridization effects, the mixing of the atomic and cage bound state wave functions, are also found, but no systematics of the hybridization present themselves. Also, in the case of Ar@C60, Inter-atomic Columbic decay (ICD) has been found and studied.
46

Studies on Vibronic Coupling in Molecules / 分子における振電相互作用に関する研究

Iwahara, Naoya 26 March 2012 (has links)
Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第16874号 / 工博第3595号 / 新制||工||1543(附属図書館) / 29549 / 京都大学大学院工学研究科分子工学専攻 / (主査)教授 田中 一義, 教授 佐藤 啓文, 教授 梶 弘典 / 学位規則第4条第1項該当
47

Synthese und Struktur-Eigenschaftsbeziehungen neuer Phthalocyanin-Sternmesogene – Ein neues Design für organische, flüssigkristalline Photovoltaikmaterialien / Synthesis and structure-property relationships of new phthalocyanine star mesogens - A new design for organic, liquid crystalline photovoltaic materials

Dechant, Moritz Thomas January 2022 (has links) (PDF)
Es wurde eine Vielzahl neuer, flüssigkristalliner Phthalocyanin-Sternmesogene synthetisiert. Die Struktur-Eigenschaftsbeziehungen und die thermotropen Eigenschaften neuer Phthalocyanin-Sternmesogene mit Freiraum sowie von sterisch überfrachteten Verbindungen wurden insbesondere hinsichtlich der Freiraumfüllung untersucht. Diesbezüglich wurde ein neuer supramolekularer, freiraumfüllender "Klick-Prozess" zwischen einem Molekül mit Freiraum und einem sterisch überfrachteten Molekül mit vier Fullerenen beobachtet. Die photophysikalischen Eigenschaften wurden zudem insbesondere im Hinblick auf die Anwendung für die Organische Photovoltaik untersucht. / A large number of new, liquid crystalline phthalocyanine star mesogens was synthesized. The structure-property relationships and the thermotropic properties of new phthalocyanine star mesogens with free space and of sterically overcrowded compounds were investigated, whereas the space-filling was of great interest. In this regard, a new supramolecular, space-filling „click-process“ between one molecule with free space and one sterically overcrowded compound with four fullerenes was observed. The photophysical properties regarding to an application for the organic photovoltaics were investigated.
48

Polycyclic Aromatic Hydrocarbons with Corannulene Subunits

Yanney, Michael 11 May 2013 (has links)
The study of polycyclic aromatic hydrocarbons (PAHs) with curved surfaces, also known as buckybowls or fullerene fragments, represent an area which is under intense investigation by organic chemists and material scientists. This dissertation describes research that contributes to this field. The availability of multi-gram quantities of the smallest buckybowl, corannulene, has led to the synthesis of several larger systems with buckybowl subunits. Cyclotrimerization of corannulyne using palladium(0) as the catalyst is described. The resulting product, C60H24, is a highly nonplanar hydrocarbon with very interesting conformational dynamics. The X-ray crystallography of the cyclotrimer confirms the “twist” conformation with C1 symmetry. The cyclotrimer also shows three distinct corannulene bowls with very different inversion barriers as confirmed by both experiment and calculations. The bowl to bowl inversion of the corannulene bowl with the lowest inversion barrier results in pseudorotation of the cyclotrimer, which gives rise to a symmetrized 1H NMR spectrum exhibiting 12 distinct proton signals. 1H NMR line shape analysis gives an estimation of the inversion barrier at 8.5 – 8.6 kcal/mol. The tetrameric hydrocarbon C80H32 was synthesized through the Diels-Alder reaction of the cyclotrimer and 1,2-didehydrocorannulene. The six membered rings adjacent to the central ring in the cyclotrimer are activated enough to react with another corannulyne. The tetramer exhibits different conformational and optical absorption properties when compared to the cyclotrimer. The tetramer (C80H32), which is highly nonplanar and sterically congested, represents the largest fully characterized oligomer of corannulyne reported to date. This is also the first reported example of a cycloaddition reaction in which a corannulene subunit acts as a diene. A tripodal molecular receptor (C87H54O6) with three corannulene pincers and a cyclotriveratrylene tether was synthesized. The molecular receptor was evaluated by 1H NMR titration in toluene-d8 for its ability to bind fullerenes. The experiment demonstrates the formation of 1:1 inclusion complexes of the molecular receptor with fullerenes and provides the association constants of 1500 plus or minus 50 and 1180 plus or minus 30 M-1 for C60 and C70, respectively.
49

Theoretical Characterization of Functional Molecular Materials

Song, Xiuneng January 2012 (has links)
Nowadays, material, energy and information technologies are three pillar industries. The materials that have close relation with our life have also been the foundation for the development of energy and information technologies. As the new member of the material family, functional molecular materials have become increasingly important for many applications, for which the design and characterization by the theoretical modeling have played the vital role. In this thesis, three different categories of functional molecular materials, the endohedral fullerenes, the fullerene derivatives and the self-assembled monolayers (SAMs), have been studied by means of first principles methods. The non-metal endohedral fullerene N@C60 is a special endohedral fullerene that is believed to be relevant to the construction of future quantum computer. The energy landscape inside the N@C60 has been carefully explored by density functional theory (DFT) calculations. The most energy favorable potential energysurfaces (PESs) for the N atom to move within the cavity have been identified. The effect of the charging on the PESs has also been examined. It is found that the inclusion of dispersion force is essential in determining the equilibriumstructure of N@C60. Furthermore, the performance of several commonly useddensity functionals with or without dispersion correction has been verified for ten different endohedral fullerenes A@C60 with the atom A being either reactive nonmetal or nobel gases elements. It shows that the inclusion of the dispersion forcedoes provide better description for the binding energy (BE), however, none ofthem could correctly describe the energy landscape inside all the ten endohedral fullerenes exclusively. It thus calls for the further improvement of current density functionals for weak interacting systems. Soft X-ray spectroscopy is a powerful tool for studying the chemical and electronic structures of functional molecular materials. Theoretical calculations have been proven to be extremely useful for providing correct assignments for spectraof large systems. In this thesis, we have performed first principles simulations forthe near-edge X-ray absorption fine structure (NEXAFS) and X-ray photoelectron spectra (XPS) of fullerene derivatives and aminothiolates SAMs. Our calculatedspectra can accurately reproduce experimental results available for all the systemsunder investigations, and identify the species or structures that are responsible for those unexpected spectral features observed in experiments. We have suggested a modified building block (MBB) approach that allows to calculate NEXAFS spectraof a large number of fullerene derivatives with very small computational cost, and resolved the long standing puzzle around the experimental XPS and NEXAFS spectra of SAMs with aminothiolates. / <p>QC 20120523</p>
50

Synthesis and Properties of Endohedral Fullerene C70 Encapsulating Two Chemical Species / 二つの化学種を内包したフラーレンC70の合成と性質

Rui, Zhang 23 March 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第20393号 / 工博第4330号 / 新制||工||1671(附属図書館) / 京都大学大学院工学研究科物質エネルギー化学専攻 / (主査)教授 村田 靖次郎, 教授 小澤 文幸, 教授 近藤 輝幸 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

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