No description available.

Thesis (Ph.D)--Chemistry and Biochemistry, Georgia Institute of Technology, 2009. / Committee Chair: Brédas, Jean-Luc; Committee Member: Janata, Jiri; Committee Member: Kippelen, Bernard; Committee Member: Marder, Seth; Committee Member: Sherrill, David. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (leaves 143-146).

No description available.

No description available.

The transition fundions for the correlated random walk with two absorbing boundaries are derived by means of a combinatorial construction which is based on Krattenthaler's Theorem for counting lattice paths with turns. Results for walks with one boundary and for unrestricted walks are presented as special cases. Finally we give an asymptotic formula, which proves to be useful for computational purposes. (author's abstract) / Series: Forschungsberichte / Institut für Statistik

Research into dye sensitised solar cells has increased in recent years as the search for a viable low cost, renewable energy source continues. The synthesis and characterisation of an array of symmetrical and asymmetrical zinc and ruthenium centred phthalocyanines and naphthalocyanines are presented in this work. Certain compounds were designed so that they would possess a carboxylic acid group which could be utilised to chemisorb the compound to a titanium dioxide surface. The dye sensitised titania electrodes were studied as potential photoanodes in dye sensitised solar cells. The use of symmetrical and asymmetrical compounds in the solar cells enabled conclusions to be drawn about the effects on electron injection of the HOMO energy level and the number and position of binding groups. The highest incident photon-to-current conversion efficiency (IPCE) of 4 % and overall conversion efficiency (η) of 0.09 % were obtained when 2,3:9,10-(22,92-carboxyl)benzo(b,k)-15,18,22,25-tetrakis(octyl)phthalocyaninatozinc(II) (63) was utilised as a sensitiser. This response was concluded to be due to the molecule possessing two binding groups and phthalocyanine like energy levels. When the ruthenium centred and zinc centred compounds were compared as sensitisers in DSCs, an increase in photovoltage and photocurrent was observed with the use of the ruthenium centred compounds. This is due to the binding group being attached to the axial ligand and therefore being situated closer to the LUMO electron density which is found at the centre of the molecule. As the binding group is closer there is less hindrance to electron injection into the TiO2 conduction band. Aggregation studies were also conducted on the acid and ester substituted zinc naphthalocyanine with and without the use of additives. It was found that the ester existed primarily as a dimer whose formation is concentration dependent. The acid also existed as a dimer but produced a "fake" monomer peak due to the formation of J aggregates. It was found that upon dilution the angle of the J aggregates shifted so that they formed face-to-face aggregates. It was found that the peripherally binding additive cetyltrimethylammonium bromide (CTAB) prevented aggregation at a concentration 20 times that of the compound but upon dilution rearranged itself so that aggregation was no longer inhibited.

Thesis (M.S.)--Brigham Young University. Dept. of Chemistry and Biochemistry, 2006. / Includes bibliographical references.

Thesis (PhD)--Montana State University--Bozeman, 2010. / Typescript. Chairperson, Graduate Committee: Aleksander Rebane. Includes bibliographical references (leaves 126-144).

The main question that has been answered in this research project is: what happens to the singularities of the S-matrix when the interaction potential becomes complex? In other words, we looked at the resonance spectral points and traced their movements on the complex momentum plane, when the imaginary part of the potential is gradually increased from zero to a certain reasonable value. This question is important in many fields of research where optical potentials are used. An optical potential can effectively take into account the loss of the beam of particles into all the reaction channels that are formally ignored. Such a simplified approach is widely used in nuclear and atomic physics. In order to study the movement of the spectral points, we used a simple potential and the Jost function method that allowed us to easily locate the spectral points as complex zeros of the Jost function. / Dissertation (MSc)--University of Pretoria, 2016. / Physics / MSc / Unrestricted