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Showing 1 to 20 of 21 for “"Vibronic coupling"”.
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To Couple or not to Couple? Exploring Vibronic Coupling in Organic Semiconductors
… with nuclear motion. In particular, vibronic coupling governs many key performance metrics, including emission linewidth, radiative efficiency, charge separation rates, and non-radiative losses. The interaction between electronic excitations and vibrational degrees of freedom not only …
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Excited states of chromophores and vibronic interactions
… focus of my Ph.D. work has been on building a vibronic coupling model for multichromophores and extending that model to more general systems. This Dissertation serves as both a summary of this work as well as a manual for the two vibronic coupling programs I have written. It is my hope that the …
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Theoretical Studies on the ultrafast photodissociation of molecules
… topology of the potential energy surfaces due to coupling between the nuclear and electron motion: termed vibronic coupling. A known feature in potential energy surfaces due to vibronic coupling is the conical intersection and these play a role in all three systems studied. In the first study we …
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Supersonic jet spectroscopy of synthetic foldamers, multichromophores, and their water containing clusters
… II modes and their amide I/I and amide II/II coupling constants. These amide I/I and amide II/II coupling constants remain similar in size for α-, β-, and γ-peptides despite the increasing number of C-C bonds separating the amide groups. These findings provide a simple, unifying picture for …
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An analysis of the photoelectron and Rydberg states of formaldehyde /|nby Carol R. Lessard. -- 260 St. Catharines [Ont.] : Dept. of Chemistry, Brock University,
… perturb each other through pseudo-Jahn-Teller vibronic coupling. The vacuum ultraviolet spectrum contains a number of features which are difficult to explain, and two unusually sharp bands can only be identified as representing some form of electron promotion in formaldehyde.
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Proton-coupled electron transfer in molecular and material catalysis
… reaction, and the results show that the vibronic coupling is dependent on the molecular geometry. This diagnostic is important for the calculation of PCET rate constants. The rate constants and kinetic isotope effects for concerted PCET in a set of hydroquinone derivatives are calculated …
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Two-photon absorption and nonlinear polariton effects in organic crystals
… a nitrogen laser-pumped dye laser. Analysis of vibronic structure reveals that the dominant intermediate states for TPA are those of B(,2) (L axis) symmetry. TPE spectra principally associated with intermediate states of A(,1) (M) symmetry exhibit strong intramolecular vibronic coupling by …
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Decoherence and Dephasing of Vibronic Excitons /
… are described as quasiparticles excitons. Coupling to vibrational degrees of freedom is often a dominating factor in the description of the exciton dynamics, therefore the vibronic exciton theory has to be used. In this thesis, the significance of dephasing and decoherence of vibronic …
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Vibroninių eksitonų išsifazavimas ir dekoherencija /
… are described as quasiparticles excitons. Coupling to vibrational degrees of freedom is often a dominating factor in the description of the exciton dynamics, therefore the vibronic exciton theory has to be used. In this thesis, the significance of dephasing and decoherence of vibronic …
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Photofragmentation of carbonyl sulfide (Ocs) following core-shell photoexcitation and photoionization
… pi* resonance indicates a strong Renner-Teller vibronic coupling of bending vibrations in the 4pi* excited states with a bent equilibrium geometry. The anions (S-, C- and O-) are observed both below and above the thresholds. The fact that the anion production is suppressed at shape resonances …
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ΦΑΣΜΑΤΟΣΚΟΠΙΑ ΔΙΕΓΕΡΜΕΝΩΝ ΗΛΕΚΤΡΟΝΙΑΚΩΝ ΚΑΤΑΣΤΑΣΕΩΝ ΤΩΝ ΠΙΚΟΛΙΝΩΝ
… LASER LIGHT WE FOUND OUT THE EXISTENCE OF VIBRONIC COUPLING BETWEEN NΠ* AND THE FIRST EXCITED ΠΠ* ELECTRONIC STATE THROUGH THE NON-TOTALLY SYMMETRIC VIBRATION 10A. WE FOUND OUT ALSO THE CHANGE OF THE GEOMETRY OF THE FIRST, MOST PROBABLY EXCITED ΠΠ* ELECTRONIC STATE ALONG THE NORMAL …
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Elektronentransferprozesse in gemischtvalenten Systemen, Redoxkaskaden und Polymeren auf Basis von Triarylaminredoxzentren
… Hush sowie einem modifizierten Modell, das der Vibronic coupling-Theorie angelehnt ist, deutet auf die Abnahme der elektronischen Kopplung mit zunehmender Vergrößerung des zentralen Phenylenspacers durch Naphthalin- (2) bzw. Anthracenspacer (3) und damit größerer sterischer Hinderung hin. …
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Four-Wave Mixing Techniques Applied to the Investigation of Non-Adiabatic Dynamics in Polyatomic Molecules
… problem was given by the decisive role that the coupling of nuclear and electronic dynamics plays in the mechanism of photochemical reactions and photobiological processes. In order to approach this complex problem, different strategies within the framework of time-resolved, four-wave mixing …
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Exploring the contributions of liquid-phase sulfur chemistry to the mass-independent sulfur fractionation of the Archean rock record
… mechanisms such as nuclear volume effects or vibronic coupling that would produce concomitant MIF in the 32S-34_3-3S triad. This provides a starting point for discussing the implications of magnetic isotope effects as a mechanism for mass-independent isotope fractionation in the chemical …
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Theoretical studies on the properties and dynamics of electronic excited states
… perturbative memory kernels for the linear vibronic coupling model, and employing them to calculate the population dynamics of the Fe(II)-Fe(III) self-exchange reaction. Finally, we present a relationship between perturbation theory traces of the spin-boson model that allows us to obtain the …
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Triplet Exciton Management via Solid-State Interactions in Organic Semiconductors
… based upon the heavy atom effect as both direct coupling between charge-transfers states and spin-vibronic coupling via an intermediate state are present.
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The Effect of The Solid-State Environment on Intramolecular Electron-Transfer Rates in Mixed-Valence Complexes (Ferrocene)
… mixed-valence biferrocenes. Furthermore, the vibronic coupling is also probably not changing very much throughout the series. It is our suggestion that the temperature dependence observed in the Mossbauer spectra of diethyl-, dipropyl-, dibutyl-, and dibenzylbiferrocenium triiodide salts …
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Electronic Structure Modelling of Singlet Fission in Organic Photovoltaics
… Furthermore, we use DFT to parametrise a linear vibronic coupling Hamiltonian of a covalent dimer of pentacene, forming the basis for many-body quantum dynamics calculations of the interplay between electronic and vibrational degrees of freedom. This reveals an interesting role for symmetry in …
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Photophysics of Hybrid Perovskites with Electroactive Molecules
… processes through inorganic–organic coupling. Central to this exploration is how structural parameters, such as linker length, molecular orientation, and dimensionality, dictate the nature and strength of this hybrid coupling. Photoinduced charge transfer and a sub-gap charge transfer …
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Spectroscopic characterization and photochemistry of nitrogen-containing molecules relevant to Titan's atmosphere
… understanding Titan's atmospheric chemistry. The vibronic spectroscopy of <em>para</em>-diisocyanobenzene (<em>p</em>DIB, C≡N-Ph-N≡C) has been characterized as a first step towards photochemical studies that can test the transformation of the isonitrile group to other nitrogen-based …
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