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851	<b>QUANTUM EFFECTS IN EXCITON TRANSPORT AND INTERACTION IN MOLECULAR AGGREGATES</b> Sarath Kumar (17544861) 05 December 2023 (has links) <p dir="ltr">Long-range exciton transport, when coupled with reduced exciton-exciton annihilation (EEA), is pivotal for the enhanced performance of organic photovoltaics and the efficiency of natural light-harvesting systems. This thesis explores strategies to optimize exciton transport and EEA rates in molecular materials by manipulating the quantum nature of excitons, particularly exciton delocalization. In addition, we also aim to understand factors limiting the transport of delocalized excitons within molecular materials. To this end, self-assembled perylene diimide (PDI) molecular aggregates are ideal candidates for this study due to their conducive properties for engineering exciton delocalization. <b>Chapter 1 </b>establishes a fundamental understanding of exciton delocalization, outlining strategies to tune this phenomenon within PDI aggregates and presenting the open questions this thesis addresses. <b>Chapter 2 </b>details the synthesis of PDI aggregates and delineates the spectroscopic techniques used for characterization, including steady-state absorption and emission, transient photoluminescence (PL), and transient absorption spectroscopy. It also describes the microscopy methods implemented to visualize exciton transport, such as transient PL microscopy and transient absorption microscopy (TAM). <b>Chapter 3 </b>introduces the thesis's primary theme: the suppression of exciton-exciton annihilation (EEA) in molecular aggregates through quantum interference. This chapter demonstrates that the spatial phase relationship of delocalized excitons is crucial in EEA, with band bottom excitons in H aggregates exhibiting an oscillating spatial phase relationship displaying a coherent suppression of EEA. <b>Chapter 4 </b>discusses how coupling to static and dynamic disorder affects coherent exciton propagation. High spatial and temporal resolution TAM experiments, along with temperature-dependent studies, help disentangle the contributions of static and dynamic disorder to exciton transport. <b>Chapter 5 </b>delves into the concept of band shape engineering, whereby the microscopic electronic couplings within PDI aggregates are fine-tuned by altering the packing motifs to regulate exciton transport. Through low-temperature TAM experiments, this chapter illustrates how the interplay between long-range Coulombic and short-range charge transfer electronic couplings can determine exciton bandwidth and influence the coherent propagation of excitons. <b>Chapter 6 </b>provides a summary of the work and discusses future directions, paving the way for continued exploration in the field of exciton transport and interaction in molecular aggregates.</p> Photochemistry Nonlinear optics and spectroscopy exciton annihilation rates exciton transport process coherent transport properties Molecular Aggregates
852	Activation of Enediynes by Photochemical Ring Contraction: Design, Synthesis and Reactivity of Cyclic Enediynes Containing Diazodicarbonyl Moiety Karpov, Grigori V. January 2006 (has links) No description available. Chemistry, Organic Photochemistry Enediynes Bergman Cyclization Ring Contraction Diazodiketones Wolff Rearrangement
853	Photoaffinity Labeling Via Nitrenium Ion Chemistry: The Photochemistry of 4-aminophenylazides Voskresenska, Valentyna D. 15 March 2011 (has links) No description available. Chemistry 4-amino-3-nitrophenyl azide
854	Early Events in Photochemistry of Aryl Azides Used as Photoaffinity Labeling Agents Panov, Maxim S. 22 November 2011 (has links) No description available. Chemistry photoaffinity labeling the photochemistry of aryl azides femtosecond spectroscopy pump-probe technique quantum chemical calculations
855	COMPUTATIONAL AND SPECTROSCOPIC STUDIES OF THE PHOTOCHEMISTRY AND PHOTOPHYSICS OF DIPHOSPHENES Peng, Huo-Lei 21 March 2007 (has links) No description available. Chemistry, Physical diphosphene phenyl twist transient absorption photochemistry substituent effect DFT
856	Photophysical Properties of Amphiphilic Naphthalene Diimide Nanoassemblies and Cadmium Sulfide Nanoparticles and Poly(phenylene-ethynylene) Nanocomposites Romano, Natalie C. January 2014 (has links) No description available. Chemistry
857	Metal-Carbon (Metal = Iridium(III) and Gold(III)) Bond Formation Under Transmetalation and Catalytic Conditions; Metallonucleosides as Anticancer Drugs and Bio-photonic Probes; and Synthesis of Iridium Fluoride Complexes. Maity, Ayan 06 February 2015 (has links) No description available. Inorganic Chemistry Chemistry Iridium Gold Cyclometalation Photochemistry Suzuki Miyaura Trans-effect Metal-Fluoride
858	Structural Characterization and Spectroscopic Investigation of Isomerization Dynamics inPhotochromic Polypyridyl Ruthenium(II) Chelating mono- and bis-Sulfoxide Complexes King, Albert W. 25 August 2015 (has links) No description available. Chemistry Physical Chemistry Inorganic Chemistry Ruthenium Sulfoxide Photochrome Isomerization Photophysics Photochemistry Ultrafast Spectroscopy
859	Ultrafast Excited State Investigation of Ruthenium and Osmium Polypyridyl SulfoxideComplexes and BOPHY Dyes Wang, Lei 17 September 2015 (has links) No description available. Chemistry ultrafast transient absorption spectroscopy ruthenium osmium polarization anisotropy photochemistry BOPHY sulfoxide
860	Design, synthesis, and characterization of photoresponsive materials usingcoordination bonds and other supramolecular interactions Razgoniaev, Anton 01 December 2017 (has links) No description available. Chemistry Polymer Chemistry Polymers Materials Science Photochemistry Chemistry Materials Science Polymer Chemistry Polymers

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