subject:(Photophysics)

University of Victoria

1. Sheepwash, Molina Audrey Lorraine. Synthesis, photophysics and photochemistry of substituted 2,7-Di-(t-butyl)-trans-10b,10c-dimethyl-10b,10c-dihydropyrenes.

Degree: Department of Chemistry, 2018, University of Victoria

URL: https://dspace.library.uvic.ca//handle/1828/10289

► The photochromism of several simple substituted and [e]-annelated 10b, 10c-dimethyl-10b, 10c-dihydropyrene derivatives was studied using steady state and time resolved fluorescence techniques as well as… (more)

Subjects/Keywords: Photochemistry; Photophysics; Metacyclophanediene; Dimethyldihydropyrenes

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APA (6^th Edition):

Sheepwash, M. A. L. (2018). Synthesis, photophysics and photochemistry of substituted 2,7-Di-(t-butyl)-trans-10b,10c-dimethyl-10b,10c-dihydropyrenes. (Thesis). University of Victoria. Retrieved from https://dspace.library.uvic.ca//handle/1828/10289

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Sheepwash, Molina Audrey Lorraine. “Synthesis, photophysics and photochemistry of substituted 2,7-Di-(t-butyl)-trans-10b,10c-dimethyl-10b,10c-dihydropyrenes.” 2018. Thesis, University of Victoria. Accessed September 16, 2019. https://dspace.library.uvic.ca//handle/1828/10289.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Sheepwash, Molina Audrey Lorraine. “Synthesis, photophysics and photochemistry of substituted 2,7-Di-(t-butyl)-trans-10b,10c-dimethyl-10b,10c-dihydropyrenes.” 2018. Web. 16 Sep 2019.

Vancouver:

Sheepwash MAL. Synthesis, photophysics and photochemistry of substituted 2,7-Di-(t-butyl)-trans-10b,10c-dimethyl-10b,10c-dihydropyrenes. [Internet] [Thesis]. University of Victoria; 2018. [cited 2019 Sep 16]. Available from: https://dspace.library.uvic.ca//handle/1828/10289.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Sheepwash MAL. Synthesis, photophysics and photochemistry of substituted 2,7-Di-(t-butyl)-trans-10b,10c-dimethyl-10b,10c-dihydropyrenes. [Thesis]. University of Victoria; 2018. Available from: https://dspace.library.uvic.ca//handle/1828/10289

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Victoria University of Wellington

2. Gallaher, Joseph. Spectroscopic investigation of excitonic and charge photogeneration processes in organic photovoltaic cells.

Degree: 2016, Victoria University of Wellington

URL: http://hdl.handle.net/10063/5251

► Organic photovoltaic (OPV) cells show significant promise as a renewable energy resource capable of meeting the world’s large and growing energy needs. Increasing device efficiency… (more)

▼ Organic photovoltaic (OPV) cells show significant promise as a renewable energy resource capable of meeting the world’s large and growing energy needs. Increasing device efficiency is central to achieving an economically viable option for widespread applications. To this end, a better understanding of the structure and dynamics of the electronic excited states is needed. In particular, the mechanism by which excitons (electron-hole pairs) escape their Coulombic attraction and generate photocurrent is yet to be established. In this thesis ultrafast laser spectroscopy, in particular transient absorption and time-resolved photoluminescence, are used to study: exciton relaxation, morphological effects on charge separation, and the pathway leading to triplet exciton states. In Chapter 3, a series of oligothiophenes are synthesised with well-defined conjugation lengths to act as molecular models of polymer backbone sub-units, and thereby probe exciton relaxation processes. Time-resolved photoluminescence (TRPL) and transient absorption (TA) spectroscopy measurements presented in Chapter 4 reveal emission signatures evolve from a mirror image of absorption - which lacks vibronic structure - towards a spectrally narrower and vibronically structured species on the hundreds of femtosecond to early picosecond timescale. Analysis of this spectral evolution shows that a broad distribution of torsional conformers is driven to rapidly planarize in the excited state, including in solid films. This provides evidence that both torsional relaxation and energy migration could contribute to the non-mirror image absorption-emission spectra observed in polymer thin films. Recently, long lived TA signatures have been attributed to triplet excited states with the suggested formation pathway being similar to organic light emitting diodes, whereby non-geminate (bimolecular) charge recombination leads to the formation of both singlet and triplet states. Isolated oligothiophenes in solution provide an ideal model system to investigate the role of structural relaxation on triplet exciton formation. Through analysis of TA spectral dynamics in Chapter 5, singlet and triplet exciton populations were tracked. Restriction of the torsional relaxation increased triplet yield suggesting vibrational hot states could drive triplet formation. This model could aid in understanding triplet exciton formation in polymer-based solar cells via spin-mixing instead of non-geminate recombination. In a series of polymer:fullerene blends, the link between the nature of polymerfullerene intermixing and charge generation pathways was investigated. It is shown in Chapter 6 that free charge generation is most efficient in a 3-phase morphology that features intimately mixed polymer:fullerene regions amongst neat polymer and fullerene phases. Distinct spectroscopic signatures made it possible to determine whether holes occupy disordered or crystalline polymer chains. TA spectral dynamics reveal the migration of holes from intermixed to pure olymer regions in 3-phase… Advisors/Committee Members: Hodgkiss, Justin.

Subjects/Keywords: Organic photovoltaics; Oligothiophenes; Polymer photophysics

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APA (6^th Edition):

Gallaher, J. (2016). Spectroscopic investigation of excitonic and charge photogeneration processes in organic photovoltaic cells. (Doctoral Dissertation). Victoria University of Wellington. Retrieved from http://hdl.handle.net/10063/5251

Chicago Manual of Style (16^th Edition):

Gallaher, Joseph. “Spectroscopic investigation of excitonic and charge photogeneration processes in organic photovoltaic cells.” 2016. Doctoral Dissertation, Victoria University of Wellington. Accessed September 16, 2019. http://hdl.handle.net/10063/5251.

MLA Handbook (7^th Edition):

Gallaher, Joseph. “Spectroscopic investigation of excitonic and charge photogeneration processes in organic photovoltaic cells.” 2016. Web. 16 Sep 2019.

Vancouver:

Gallaher J. Spectroscopic investigation of excitonic and charge photogeneration processes in organic photovoltaic cells. [Internet] [Doctoral dissertation]. Victoria University of Wellington; 2016. [cited 2019 Sep 16]. Available from: http://hdl.handle.net/10063/5251.

Council of Science Editors:

Gallaher J. Spectroscopic investigation of excitonic and charge photogeneration processes in organic photovoltaic cells. [Doctoral Dissertation]. Victoria University of Wellington; 2016. Available from: http://hdl.handle.net/10063/5251

University of Minnesota

3. Hinkle, Lindsay Marie. Crystalline transition metal-based sensors for the optical detection of oxygen.

Degree: PhD, Chemistry, 2012, University of Minnesota

URL: http://purl.umn.edu/158333

► Oxygen is essential to life, motivating the development of optical oxygen sensors. Current sensing methods rely on either electrochemical measurements or an optical response from… (more)

▼ Oxygen is essential to life, motivating the development of optical oxygen sensors. Current sensing methods rely on either electrochemical measurements or an optical response from solutions or polymer based materials. These techniques often suffer from support degradation, oxygen consumption, and response plots that are difficult to interpret. A promising alternative to current optical sensing technologies are porous crystalline solids, as these solids provide a consistent emission site along with the necessary open space to facilitate diffusion of molecular oxygen through the material. This thesis explores neutral, mono-, di-, and tricationic coordination complexes for use as solid-state devices to detect oxygen. This series of transition metal complexes was synthesized, and the packing motifs studied by single crystal X-ray diffraction. After investigating the crystalline packing, photophysical properties, and sensitivity of emission toward oxygen, it was determined that the mono- and dicationic complexes are the most promising materials based on their sensitivity and long term stability. In Chapter 1, a brief introduction to oxygen sensing and the goals of this project are given. In Chapter 2, the synthesis and characterization of a series of neutral zinc(II) compounds are reported. One specific compound, Zn(terpy-*)Br₂ (where terpy-* = 4,4',4''-tri-tert-butyl-2,2':6',2''-terpyridine) showed promise for detecting small oxygen concentrations. However, stability testing determined the compound was not stable toward LED illumination and oxygen exposure. In Chapter 3, a monocationic family of compounds based on the [Cu(P^P)(N^N)]⁺ core (where P^P is a bidentate phosphine and N^N is a bidentate amine) was explored. After the sensing ability of the compounds was determined, their stability was rigorously tested. The studies demonstrate that compounds with tfpb^- (where tfpb^- = tetrakis[bis-3,5-trifluoromethyl(phenylborate)]) counterions were typically more stable and more sensitive to changes in oxygen than their BF₄^- and pfpb^- (pfpb^- = tetrakis-(pentafluorophenyl)borate) counterparts. Additionally, a mechanism for the degradation of these sensors is proposed. In Chapter 4, a zinc(II) dicationic polypyridine complex was tested and compared to a previously reported and analogous ruthenium(II) compound. Based on the knowledge that similarly shaped molecules tend to pack in a similar way, it was hypothesized that crystalline materials of both the Ru(II) and Zn(II) compounds would pack similarly and therefore sense oxygen in a similar manner. Even though the compounds crystallize in a similar manner and the trends in oxygen sensitivity are the same, the K_SV parameters were not as similar as was predicted. The difference in sensing ability is due to a different quenching mechanism in the Ru(II) and Zn(II) complexes. Nonetheless, the Zn(II) family of compounds is a reliable and…

Subjects/Keywords: Crystallography; Oxygen detection; Photophysics

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APA (6^th Edition):

Hinkle, L. M. (2012). Crystalline transition metal-based sensors for the optical detection of oxygen. (Doctoral Dissertation). University of Minnesota. Retrieved from http://purl.umn.edu/158333

Chicago Manual of Style (16^th Edition):

Hinkle, Lindsay Marie. “Crystalline transition metal-based sensors for the optical detection of oxygen.” 2012. Doctoral Dissertation, University of Minnesota. Accessed September 16, 2019. http://purl.umn.edu/158333.

MLA Handbook (7^th Edition):

Hinkle, Lindsay Marie. “Crystalline transition metal-based sensors for the optical detection of oxygen.” 2012. Web. 16 Sep 2019.

Vancouver:

Hinkle LM. Crystalline transition metal-based sensors for the optical detection of oxygen. [Internet] [Doctoral dissertation]. University of Minnesota; 2012. [cited 2019 Sep 16]. Available from: http://purl.umn.edu/158333.

Council of Science Editors:

Hinkle LM. Crystalline transition metal-based sensors for the optical detection of oxygen. [Doctoral Dissertation]. University of Minnesota; 2012. Available from: http://purl.umn.edu/158333

Temple University

4. Spata, Vincent Anthony. PHOTOINITIATED-PROCESSES IN ADENINE OLIGONUCLEOTIDES: EXAMINING THE NATURE OF π-STACKING INTERACTIONS IN MULTI-CHROMOPHORE SYSTEMS.

Degree: PhD, 2016, Temple University

URL: http://digital.library.temple.edu/u?/p245801coll10,388262

►

Chemistry

DNA provides the genetic code which is almost universal in all living organisms. When DNA is exposed to ultra-violet light it can cause cell… (more)

▼

Chemistry

DNA provides the genetic code which is almost universal in all living organisms. When DNA is exposed to ultra-violet light it can cause cell degradation and mutation which are two of the major causes which lead to cancer. The nature of decay in DNA oligomers is a widely studied topic. Fluorescence and Transient Absorption (TA) experiments on polynucleotides which compare the behavior of the decay to the monomer bases have revealed the presence of longer-lived components in the multimeric systems. There has been heated debate over the character of the excited states responsible for the long-lived signals. Theoretical methods are well suited to compliment experiment by providing a description of processes and physical properties on the molecular level. We have studied π-stacked adenines in the gas-phase with Quantum Mechanical (QM) methods, but also in the helical environment using high-level ab initio methods, classical simulations and the combination of the two (QM/MM). Inclusion of the environmental interactions dramatically alters the shape of the potential energy surfaces due to steric interactions from the backbone and interactions with the surrounding bases and environment. This work examines the complete picture of photophysical processes occurring in adenine oligonucleotides within the helical environment after the absorption of a photon: the nature of initial absorption and the subsequent radiative and non-radiative decay pathways. It contributes key discoveries inherent to the mechanisms which govern photo-initiated processes in DNA, and also contributes to our fundamental knowledge of the photophysical behavior of π-stacked chromophores. The work reveals the effects of π-stacking interactions and the environment on photo-initiated processes in oligonucleotides. It reveals that excitonic coupling is responsible for the key differences in features in the absorption spectrum of adenine oligomers compared to the isolated bases, illustrates the role of charge transfer (CT) mixing in both absorption and decay processes, and the importance of bonded excimers in deactivation. The work also illustrates that CT excimers are responsible for the long-lived signals evidenced in Transient Absorption and Fluorescence experiments and that neutral excimers can exist within the DNA helical environment. It also adds to the discussion in the field on the nature of photodecay mechanisms occurring within the DNA helix.

Temple University – Theses

Advisors/Committee Members: Matsika, Spiridoula;, Spano, Francis C., Stanley, Robert J., Perdew, John P.;.

Subjects/Keywords: Physical chemistry;

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APA (6^th Edition):

Spata, V. A. (2016). PHOTOINITIATED-PROCESSES IN ADENINE OLIGONUCLEOTIDES: EXAMINING THE NATURE OF π-STACKING INTERACTIONS IN MULTI-CHROMOPHORE SYSTEMS. (Doctoral Dissertation). Temple University. Retrieved from http://digital.library.temple.edu/u?/p245801coll10,388262

Chicago Manual of Style (16^th Edition):

Spata, Vincent Anthony. “PHOTOINITIATED-PROCESSES IN ADENINE OLIGONUCLEOTIDES: EXAMINING THE NATURE OF π-STACKING INTERACTIONS IN MULTI-CHROMOPHORE SYSTEMS.” 2016. Doctoral Dissertation, Temple University. Accessed September 16, 2019. http://digital.library.temple.edu/u?/p245801coll10,388262.

MLA Handbook (7^th Edition):

Spata, Vincent Anthony. “PHOTOINITIATED-PROCESSES IN ADENINE OLIGONUCLEOTIDES: EXAMINING THE NATURE OF π-STACKING INTERACTIONS IN MULTI-CHROMOPHORE SYSTEMS.” 2016. Web. 16 Sep 2019.

Vancouver:

Spata VA. PHOTOINITIATED-PROCESSES IN ADENINE OLIGONUCLEOTIDES: EXAMINING THE NATURE OF π-STACKING INTERACTIONS IN MULTI-CHROMOPHORE SYSTEMS. [Internet] [Doctoral dissertation]. Temple University; 2016. [cited 2019 Sep 16]. Available from: http://digital.library.temple.edu/u?/p245801coll10,388262.

Council of Science Editors:

Spata VA. PHOTOINITIATED-PROCESSES IN ADENINE OLIGONUCLEOTIDES: EXAMINING THE NATURE OF π-STACKING INTERACTIONS IN MULTI-CHROMOPHORE SYSTEMS. [Doctoral Dissertation]. Temple University; 2016. Available from: http://digital.library.temple.edu/u?/p245801coll10,388262

Dublin City University

5. Sewell , Gavin. Zeolite-Y scaffolded donor-acceptor systems for nanoelectronics.

Degree: School of Chemical Sciences, 2014, Dublin City University

URL: http://doras.dcu.ie/19759/

► Zeolites can act as hosts for supramolecular organization of molecules and complexes. A key objective in supramolecular chemistry is the development of donor acceptor systems… (more)

▼ Zeolites can act as hosts for supramolecular organization of molecules and complexes. A key objective in supramolecular chemistry is the development of donor acceptor systems capable of controlled photoinduced electron and energy transfer. This thesis focuses on a fundamental study of the capacity of zeolite materials to accommodate dipolar communication between metal complex guest species as well as exploring the effect of zeolite materials on the photophysical properties of guest molecules. Chapter 1 and 2 outline the current state of zeolite host-guest chemistry and the experimental procedures and instrumentation ultilised in this work. Chapter 3 investigates the ability of Y-zeolite to accommodate energy transfer processes between co-doped donors and acceptors. A series of [Ru(bpy)3]2+ (where bpy is 2,2’-bipyridine) doped Zeolite Y materials co-doped with iron polypyridyl complexes [Fe(bpy)3]2+ and [Fe(tpy)2]2+ were prepared via the ‘ship in a bottle’ syntesis. The co-encapsulated [Ru(bpy)3]2+ complex undergoes efficient energy transfer to both iron polypyridyl complexes over distances of between of 32 Å and 27 Å. Chapter 4 examines the influence of zeolite-Y entrapment upon the photophysical properties of the Iridium (III) polypyridyl complexes [Ir(bpy)3]3+ and [Ir(tpy)2]3+. Their preparation and photophysical characterization is described. Dramatic changes in the emission spectra of the complexes were observed due to both the polarity of the zeolite interior as well as distortions caused by tight steric confinement. Chapter 5 quantifies the extent of the excited state distortion of guest molecules entrapped within the pores of zeolite-Y by Huang-Rhys analysis. It was found that the zeolite environment impacts on the excited state geometry of the complexes generally limiting the amount of structural distortion the complex can undergo. In Chapter 6, iridium polypyridyl complexes in a zeolite-Y matrix were codoped with europium bis-bipyridine. The photophysical properties of these materials were studied and indicated that sensitisation of the zeolite included europium acceptor by a co-included iridium polypyridyl energy donor complex occurred. Chapter 7 offers conclusions on this thesis and outlines future work. Advisors/Committee Members: Keyes, Tia E., IRCSET.

Subjects/Keywords: Photochemistry; Inorganic chemistry; Nanotechnology; Chemistry; Zeolite; Photophysics

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APA (6^th Edition):

Sewell , G. (2014). Zeolite-Y scaffolded donor-acceptor systems for nanoelectronics. (Thesis). Dublin City University. Retrieved from http://doras.dcu.ie/19759/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Sewell , Gavin. “Zeolite-Y scaffolded donor-acceptor systems for nanoelectronics.” 2014. Thesis, Dublin City University. Accessed September 16, 2019. http://doras.dcu.ie/19759/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Sewell , Gavin. “Zeolite-Y scaffolded donor-acceptor systems for nanoelectronics.” 2014. Web. 16 Sep 2019.

Vancouver:

Sewell G. Zeolite-Y scaffolded donor-acceptor systems for nanoelectronics. [Internet] [Thesis]. Dublin City University; 2014. [cited 2019 Sep 16]. Available from: http://doras.dcu.ie/19759/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Sewell G. Zeolite-Y scaffolded donor-acceptor systems for nanoelectronics. [Thesis]. Dublin City University; 2014. Available from: http://doras.dcu.ie/19759/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – Berkeley

6. Lewis, Nicholas Henry Cohen. Two-Dimensional Electronic-Vibrational Spectroscopy.

Degree: Chemistry, 2016, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/3np6394x

► This dissertation describes the development and initial applications of Two-Dimensional Electronic-Vibrational spectroscopy (2DEV), a multidimensional ultrafast spectroscopic technique that is capable of directly probing the… (more)

▼ This dissertation describes the development and initial applications of Two-Dimensional Electronic-Vibrational spectroscopy (2DEV), a multidimensional ultrafast spectroscopic technique that is capable of directly probing the coupling between electronic and vibrational transitions in molecular species.This thesis first provides the necessary background and motivation driving the development of this spectroscopy, discussing the role of electronic-vibrational coupling in small molecule photophysics and the ways we can take advantage of these physics to study electronic excitation transfer in photosynthetic light harvesting systems. It then discusses the details of the apparatus constructed to perform the 2DEV experiments, as well as some of the important aspects of the signal processing and extraction of the desired signal, using phase cycling techniques. It goes on to describe the development of a simple model to be used in understanding the new information content accessible with 2DEV, and presents experimental results from the laser dye DTTCI. The basic predictions of the model, such as the dynamics of the spectral lineshape, are shown to hold in these experimental results, and we provide an experimental measurement for the difference in the strength of the vibration-bath coupling between the electronic ground and excited states.In chapter 4, the model is extended to the case of an electronically coupled dimer, and a method is proposed by which 2DEV could potentially be used to study the movement of electronic excitations through a molecular aggregate, such as a photosynthetic light harvesting complex. It is shown how it might be possible to measure the electronic excited state populations directly in the site basis, without the need for an accompanying model. To demonstrate an experimental implementation of this method, the 2DEV spectra of Chlorophyll a and b in solution are then presented, assigning the important spectral features and demonstrating conclusively the connection between spectral shifts along the electronic and vibrational axes due to changes in the axial coordination state of the central Mg. This is a first step which is then expanded upon with the demonstration of the experimental application of 2DEV to the major light harvesting complex in plants, LHCII, and an illustration that the technique proposed in chapter 4 is technically sound. Indications are observed of long lived population of Chl b which contradicts the predictions of current models for the excitonic structure of this system, and calls into question our current understanding of the initial energy transfer dynamics in plant photosynthesis.Finally, a discussion is provided of some of the promising directions for 2DEV to be further developed in the future.

Subjects/Keywords: Chemistry; Physical chemistry; Photophysics; Photosynthesis; Spectroscopy

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APA (6^th Edition):

Lewis, N. H. C. (2016). Two-Dimensional Electronic-Vibrational Spectroscopy. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/3np6394x

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Lewis, Nicholas Henry Cohen. “Two-Dimensional Electronic-Vibrational Spectroscopy.” 2016. Thesis, University of California – Berkeley. Accessed September 16, 2019. http://www.escholarship.org/uc/item/3np6394x.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Lewis, Nicholas Henry Cohen. “Two-Dimensional Electronic-Vibrational Spectroscopy.” 2016. Web. 16 Sep 2019.

Vancouver:

Lewis NHC. Two-Dimensional Electronic-Vibrational Spectroscopy. [Internet] [Thesis]. University of California – Berkeley; 2016. [cited 2019 Sep 16]. Available from: http://www.escholarship.org/uc/item/3np6394x.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Lewis NHC. Two-Dimensional Electronic-Vibrational Spectroscopy. [Thesis]. University of California – Berkeley; 2016. Available from: http://www.escholarship.org/uc/item/3np6394x

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Virginia Tech

7. Rowe, Jennifer Maria. Luminescent Properties of Anthracene-based Metal-Organic Frameworks.

Degree: MS, Chemistry, 2016, Virginia Tech

URL: http://hdl.handle.net/10919/71684

► Metal-organic frameworks (MOFs) are crystalline materials composed of metal clusters and organic ligands. MOFs that exhibit photoluminescence are promising materials for a broad range of… (more)

▼ Metal-organic frameworks (MOFs) are crystalline materials composed of metal clusters and organic ligands. MOFs that exhibit photoluminescence are promising materials for a broad range of applications. Due to their structural tunability and crystalline nature, luminescent MOFs also provide an excellent platform for studying structure–property relationships of materials. The photophysical properties of three anthracene-dicarboxylic acids – 1,4-anthracene dicarboxylic acid (1,4-ADCA), 2,6-anthracene dicarboxylic acid (2,6-ADCA) and 9,10-anthracene dicarboxylic acid (9,10-ADCA) – were studied in a series of polar aprotic solvents using steady-state absorption, steady-state emission spectroscopy and time-correlated single photon counting (TCSPC) emission lifetime spectroscopy. The addition of carboxylic acid functional groups on the anthracene ring alters photophysical properties to varying degrees depending on the location and protonation state. Density functional theory (DFT) calculations reveal that the lowest-energy ground-state structures of both 2,6-ADCA and 1,4-ADCA have dihedral angles between the carboxylic acids and aromatic planes of θ = 0°, while the same dihedral angle increases to θ = 56.6° for 9,10-ADCA. Time-dependent DFT calculations suggest that the carboxyl groups of 1,4-ADCA and 2,6-ADCA remain coplanar with the anthracene ring system in the excited state. In contrast, the calculations reveal significant changes between the ground and excited geometries for 9,10-ADCA and puckering of the anthracene moiety of is observed. The three anthracene dicarboxylic acids were then incorporated into zirconium-based MOFs. The MOF structures were characterized using powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM). The steady-state absorption and emission spectra as well as the fluorescence lifetimes of the MOFs were compared to that of the corresponding ligand in solution. The MOFs comprising 9,10-ADCA and 2,6-ADCA formed highly crystalline octahedral shaped crystals and were found to be isostructural with the well-known UiO-66 and UiO-67 frameworks. However, incorporation of the 1,4-ADCA ligand resulted in large rod-shaped crystals. The absorption spectra of the MOFs are broadened and redshifted compared with that of the corresponding free ligands. The emission spectra of the MOFs constructed from 9,10-ADCA and 1,4-ADCA display emission bands that resemble that of the free ligand in acidic solutions, but are slightly broadened and redshifted in the MOF. Little difference is observed between that of 2,6-ADCA within the MOF and in acidic solution. The broadening and redshift observed in the absorption and emission is indicative of intermolecular interactions between anthracene units and/or with the Zr4+ clusters. The fluorescence lifetimes measured for the anthracene-based MOFs show a long component, comparable to the lifetime of the free ligand, along with shorter component. This may also suggest intermolecular interactions between chromophores in the MOFs. Altogether, derivatization of… Advisors/Committee Members: Morris, Amanda (committeechair), Morris, John R. (committee member), Tissue, Brian M. (committee member).

Subjects/Keywords: Metal-Organic Frameworks; luminescence; photophysics; anthracene

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APA (6^th Edition):

Rowe, J. M. (2016). Luminescent Properties of Anthracene-based Metal-Organic Frameworks. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/71684

Chicago Manual of Style (16^th Edition):

Rowe, Jennifer Maria. “Luminescent Properties of Anthracene-based Metal-Organic Frameworks.” 2016. Masters Thesis, Virginia Tech. Accessed September 16, 2019. http://hdl.handle.net/10919/71684.

MLA Handbook (7^th Edition):

Rowe, Jennifer Maria. “Luminescent Properties of Anthracene-based Metal-Organic Frameworks.” 2016. Web. 16 Sep 2019.

Vancouver:

Rowe JM. Luminescent Properties of Anthracene-based Metal-Organic Frameworks. [Internet] [Masters thesis]. Virginia Tech; 2016. [cited 2019 Sep 16]. Available from: http://hdl.handle.net/10919/71684.

Council of Science Editors:

Rowe JM. Luminescent Properties of Anthracene-based Metal-Organic Frameworks. [Masters Thesis]. Virginia Tech; 2016. Available from: http://hdl.handle.net/10919/71684

University of Oxford

8. Gryte, Kristofer. Analysis methods for single molecule fluorescence spectroscopy.

Degree: PhD, 2012, University of Oxford

URL: http://ora.ox.ac.uk/objects/uuid:148969c6-78aa-49c2-8f0e-2d5e5018fd98 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.581115

► This thesis describes signal analysis methods for single-molecule fluorescence data. The primary factor motivating method development is the need to distinguish single-molecule FRET fluctuations due… (more)

▼ This thesis describes signal analysis methods for single-molecule fluorescence data. The primary factor motivating method development is the need to distinguish single-molecule FRET fluctuations due to conformational dynamics from fluctuations due to distance-independent FRET changes. Single-molecule Förster resonance energy transfer (FRET) promises a distinct advantage compared to alternative biochemical methods in its potential to relate biomolecular structure to function. Standard measurements assume that the mean transfer efficiency between two fluorescent probes, a donor and an acceptor, corresponds to the mean donor-acceptor distance, thus providing structural information. Accordingly, measurement analysis assumes that mean transfer efficiency fluctuations entail mean donor-acceptor distance fluctuations. Detecting such fluctuations is important in resolving molecular dynamics, as molecular function often necessitates structural changes. A problem arises, however, in that factors other than donor-acceptor distance changes may induce mean transfer efficiency fluctuations. We refer to these factors as distance-independent FRET changes. We present analysis methods to detect distance-independent photophysical dynamics and to determine their correlation with distance-dependent FRET dynamics. First, we review a theory of photon statistics and show how we can use the theory to detect FRET fluctuations. Second, we extend the theory to alternating laser excitation (ALEx) measurements and demonstrate how fluorophore stoichiometry, a measure of fluorophore brightness, reports on distance-independent photophysical dynamics. Next, we provide a measure to determine the extent to which stoichiometry fluctuations account for FRET dynamics. Finally, we use a framework similar to the preceding along with recent advances in the theory of total internal reflection fluorescence (TIRF) microscopy FRET measurements to detect TIRF FRET fluctuations which occur on a timescale faster than the measurement temporal resolution. We validate our methods with simulations and demonstrate their utility in delineating RNA polymerase open complex conformational dynamics.

Subjects/Keywords: 543.56; Biophysics; Time-Series Analysis; confocal; Photophysics

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APA (6^th Edition):

Gryte, K. (2012). Analysis methods for single molecule fluorescence spectroscopy. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:148969c6-78aa-49c2-8f0e-2d5e5018fd98 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.581115

Chicago Manual of Style (16^th Edition):

Gryte, Kristofer. “Analysis methods for single molecule fluorescence spectroscopy.” 2012. Doctoral Dissertation, University of Oxford. Accessed September 16, 2019. http://ora.ox.ac.uk/objects/uuid:148969c6-78aa-49c2-8f0e-2d5e5018fd98 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.581115.

MLA Handbook (7^th Edition):

Gryte, Kristofer. “Analysis methods for single molecule fluorescence spectroscopy.” 2012. Web. 16 Sep 2019.

Vancouver:

Gryte K. Analysis methods for single molecule fluorescence spectroscopy. [Internet] [Doctoral dissertation]. University of Oxford; 2012. [cited 2019 Sep 16]. Available from: http://ora.ox.ac.uk/objects/uuid:148969c6-78aa-49c2-8f0e-2d5e5018fd98 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.581115.

Council of Science Editors:

Gryte K. Analysis methods for single molecule fluorescence spectroscopy. [Doctoral Dissertation]. University of Oxford; 2012. Available from: http://ora.ox.ac.uk/objects/uuid:148969c6-78aa-49c2-8f0e-2d5e5018fd98 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.581115

Wesleyan University

9. Moreno, Andrew Thomas. The Photophysical Characterization of the Guanine Analogue 6-methylisoxanthopterin in DNA Oligomers and Its Application to Probing DNA-Protein Interactions.

Degree: Chemistry, 2014, Wesleyan University

URL: https://wesscholar.wesleyan.edu/etd_diss/41

Subjects/Keywords: photophysics; DNA; protein

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Moreno, A. T. (2014). The Photophysical Characterization of the Guanine Analogue 6-methylisoxanthopterin in DNA Oligomers and Its Application to Probing DNA-Protein Interactions. (Doctoral Dissertation). Wesleyan University. Retrieved from https://wesscholar.wesleyan.edu/etd_diss/41

Chicago Manual of Style (16^th Edition):

Moreno, Andrew Thomas. “The Photophysical Characterization of the Guanine Analogue 6-methylisoxanthopterin in DNA Oligomers and Its Application to Probing DNA-Protein Interactions.” 2014. Doctoral Dissertation, Wesleyan University. Accessed September 16, 2019. https://wesscholar.wesleyan.edu/etd_diss/41.

MLA Handbook (7^th Edition):

Moreno, Andrew Thomas. “The Photophysical Characterization of the Guanine Analogue 6-methylisoxanthopterin in DNA Oligomers and Its Application to Probing DNA-Protein Interactions.” 2014. Web. 16 Sep 2019.

Vancouver:

Moreno AT. The Photophysical Characterization of the Guanine Analogue 6-methylisoxanthopterin in DNA Oligomers and Its Application to Probing DNA-Protein Interactions. [Internet] [Doctoral dissertation]. Wesleyan University; 2014. [cited 2019 Sep 16]. Available from: https://wesscholar.wesleyan.edu/etd_diss/41.

Council of Science Editors:

Moreno AT. The Photophysical Characterization of the Guanine Analogue 6-methylisoxanthopterin in DNA Oligomers and Its Application to Probing DNA-Protein Interactions. [Doctoral Dissertation]. Wesleyan University; 2014. Available from: https://wesscholar.wesleyan.edu/etd_diss/41

University of North Texas

10. Determan, John J. Photophysics and Photochemistry of Copper(I) Phosphine and Collidine Complexes: An Experimental/Theoretical Investigation.

Degree: 2011, University of North Texas

URL: https://digital.library.unt.edu/ark:/67531/metadc84199/

► Copper(I) complexes have been studied through both experimental and computational means in the presented work. Overall, the work focuses on photophysical and photochemical properties of… (more)

Subjects/Keywords: Copper(I) complexes; OLED; luminescence; photochemistry; photophysics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Determan, J. J. (2011). Photophysics and Photochemistry of Copper(I) Phosphine and Collidine Complexes: An Experimental/Theoretical Investigation. (Thesis). University of North Texas. Retrieved from https://digital.library.unt.edu/ark:/67531/metadc84199/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Determan, John J. “Photophysics and Photochemistry of Copper(I) Phosphine and Collidine Complexes: An Experimental/Theoretical Investigation.” 2011. Thesis, University of North Texas. Accessed September 16, 2019. https://digital.library.unt.edu/ark:/67531/metadc84199/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Determan, John J. “Photophysics and Photochemistry of Copper(I) Phosphine and Collidine Complexes: An Experimental/Theoretical Investigation.” 2011. Web. 16 Sep 2019.

Vancouver:

Determan JJ. Photophysics and Photochemistry of Copper(I) Phosphine and Collidine Complexes: An Experimental/Theoretical Investigation. [Internet] [Thesis]. University of North Texas; 2011. [cited 2019 Sep 16]. Available from: https://digital.library.unt.edu/ark:/67531/metadc84199/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Determan JJ. Photophysics and Photochemistry of Copper(I) Phosphine and Collidine Complexes: An Experimental/Theoretical Investigation. [Thesis]. University of North Texas; 2011. Available from: https://digital.library.unt.edu/ark:/67531/metadc84199/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

11. Inglez, Simone Delezuk. Propriedades fotoquímicas e fotofísicas, e investigação teórica de um novo monômero-complexo de Ru(II)-bipiridina.

Degree: PhD, Química Analítica, 2008, University of São Paulo

URL: http://www.teses.usp.br/teses/disponiveis/75/75132/tde-18042008-171406/ ;

► As sínteses, o cálculo do OM, as propriedades fotoquímicas e fotofísicas dos complexos cis-[Ru(bpy)2(L)x](PF6)2, onde a bpy é 2,2\'-bipiridina e L é 5,6-bis(3-amidopiridina)-7-oxanorborneno (3amdpy2oxaNBE, complexo… (more)

▼ As sínteses, o cálculo do OM, as propriedades fotoquímicas e fotofísicas dos complexos cis-[Ru(bpy)2(L)x](PF6)2, onde a bpy é 2,2\'-bipiridina e L é 5,6-bis(3-amidopiridina)-7-oxanorborneno (3amdpy2oxaNBE, complexo 2) ou 3-aminopiridina (3amnpy; complexo 3) foram estudados. 3amdpy2oxaNBE é o novo ligante quelato 5,6-bis(3-amidopiridina)-7-oxanorborneno (1) e apresenta duas amidas piridinas substituídas -conectadas ao monômero oxanorborneno - que são originadas da reação da 3amnpy e do monômero 5,6-bis-carboxilato-7-oxanorborneno. Os complexos 2 e 3 exibem absorções na região de 350 nm e entre 420-500 nm, atribuídas a uma contribuição das transições MLCT (dπ →bpy and dπ →L; L = 3amdpy2oxaNBE ou 3amnpy). Fotólise do complexo 3 levou ao cis-[Ru(bpy)2(3amnpy)(solvente)]2+, enquanto o complexo 2 é inerte à fotossubstituíção. Os comprimentos de onda de irradiação (330 > 440 > 500 nm) e os solventes (DMF > CH3CN > CH2Cl2 ~ THF) influenciam na fotolabilidade do complexo 3. A formação de cis-[Ru(bpy)2(CH3CN)2]2+ foi observada por RMN de 1H quando o complexo 3 foi irradiado em 420 nm em CH3CN. A emissão do complexo 2, em 594 nm, é atribuída como uma emissão MLCT (Ru →bpy) e é caracterizada por um tempo de vida longo à temperatura ambiente (650 ns em CH3CN e 509 ns em H2O). A emissão é independente do λirr, mas é dependente da temperatura, i.e., aumenta quando a temperatura é abaixada. Considerando-se que o anel quelato de 1 contribui para a estabilidade do complexo 2 sob irradiação de luz contínua, a diferença nos fotoprocessos primários de 3 (perda da 3amnpy) e 2 (luminescência) pode ser explicada pela influência de L na energia da banda de CT Ru →bpy. Para 2, o estado excitado Ru →bpy é o de mais baixa energia e o complexo é luminescente e inerte à fotossubstituição. Para o complexo 3, é possível mover a banda de absorção de CT Ru →bpy para uma posição comparável à da banda de MC mais abaixo. A eficiência da fotossubstituição é muito pequena quando o estado de TC é mais baixo, e razoavelmente grande quando o estado MC é mais baixo na energia. Esses resultados são corroborados pelo cálculo de TDDFT, que mostra a transição MC em 328 nm (3,78 eV) para 3. Então, a modificação na substituição do grupo piridina levou a uma diferença crucial nos fotoprocessos primários entre os dois complexos. No complexo 2, a depopulação eletrônica da unidade {RuII(bpy)2} e a população de um orbital da bpy* por meio da excitação são evidentes pela comparação com as propriedades fotofísicas com complexos relacionados com [Ru(bpy)3]2+. Além disso, uma redução de um ligante bpy no estado excitado MLCT é indicada pelo espectro resolvido no tempo em que mostrou características típicas da bpy.-. As propriedades fotocatalíticas de 2 são espectroscopicamente demonstradas pela supressão oxidativa usando-se os íons receptores de elétrons metilviologênio2+ ou [RuCl(NH3)5]+2.Também foi realizado um estudo cinético da reação de desacetilação assistida por ultra-som. Com base nos resultados de %GA das amostras de… Advisors/Committee Members: Lima Neto, Benedito dos Santos.

Subjects/Keywords: complexo de rutênio; fotofísica; fotoquímica; photochemistry; photophysics; ruthenium complex

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Inglez, S. D. (2008). Propriedades fotoquímicas e fotofísicas, e investigação teórica de um novo monômero-complexo de Ru(II)-bipiridina. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/75/75132/tde-18042008-171406/ ;

Chicago Manual of Style (16^th Edition):

Inglez, Simone Delezuk. “Propriedades fotoquímicas e fotofísicas, e investigação teórica de um novo monômero-complexo de Ru(II)-bipiridina.” 2008. Doctoral Dissertation, University of São Paulo. Accessed September 16, 2019. http://www.teses.usp.br/teses/disponiveis/75/75132/tde-18042008-171406/ ;.

MLA Handbook (7^th Edition):

Inglez, Simone Delezuk. “Propriedades fotoquímicas e fotofísicas, e investigação teórica de um novo monômero-complexo de Ru(II)-bipiridina.” 2008. Web. 16 Sep 2019.

Vancouver:

Inglez SD. Propriedades fotoquímicas e fotofísicas, e investigação teórica de um novo monômero-complexo de Ru(II)-bipiridina. [Internet] [Doctoral dissertation]. University of São Paulo; 2008. [cited 2019 Sep 16]. Available from: http://www.teses.usp.br/teses/disponiveis/75/75132/tde-18042008-171406/ ;.

Council of Science Editors:

Inglez SD. Propriedades fotoquímicas e fotofísicas, e investigação teórica de um novo monômero-complexo de Ru(II)-bipiridina. [Doctoral Dissertation]. University of São Paulo; 2008. Available from: http://www.teses.usp.br/teses/disponiveis/75/75132/tde-18042008-171406/ ;

12. Pinto, Leticia Felipe Abdias. Preparação e caracterização fotoquímica de derivado de S,S-dioxidotioxantona: aplicações em fotopolimerização.

Degree: PhD, Físico-Química, 2013, University of São Paulo

URL: http://www.teses.usp.br/teses/disponiveis/75/75131/tde-24022014-114205/ ;

►

Neste trabalho foi realizada a síntese e caracterização de um derivado de S,S-dioxidotioxantona, 7,8-benzotioxanton-9-ona-10,10-dióxido (TX-Np-SO2). A TX-Np-SO2 foi caracterizada estruturalmente por espectros eletrônico e vibracional… (more)

▼

Neste trabalho foi realizada a síntese e caracterização de um derivado de S,S-dioxidotioxantona, 7,8-benzotioxanton-9-ona-10,10-dióxido (TX-Np-SO2). A TX-Np-SO2 foi caracterizada estruturalmente por espectros eletrônico e vibracional (UV-vis e fluorescência, Infravermelho) e também por ressonância magnética nuclear (RMN) de 1H e 13C. As propriedades fotofísicas, espectros de emissão de fluorescência e fosforescência e o rendimento quântico de fluorescência da TX-Np-SO2 foram determinadas, assim como os tempos de vida de fluorescência (τF = 3,62 ns) e fosforescência (τPh = 800 ms). Os espectros de absorção triplete-triplete dos transientes da TX-Np-SO2, em soluções desoxigenadas de metanol, acetonitrila e metilciclohexano, foram determinados por Fotólise por Pulso de Laser, bem como as constantes de velocidade de supressão bimoleculares do derivado pelos supressores trans-estilbeno, trietilamina, p-dimetilamina benzoato de etila e 2-propanol. A fotopolimerização do metacrilato de metila (MMA) iniciada por TX-Np-SO2 foi estudada por dilatometria. A reação de polimerização do iniciador (TX-Np-SO2) na presença de amina e o monômero MMA foi estudada de modo a determinar a taxa de polimerização (Rp) a diferentes concentrações de trietilamina (TEA) e p-dimetilamina benzoato de etila (EDB).

The aim of this work was the synthesis and characterization of a S,S-dioxidethioxanthone derivative, 7,8-benzo-thioxanthen-9-one-10,10-dioxide (TX-Np-SO2). The TX-Np-SO2 was structurally characterized by its electronic and vibrational spectra (UV-vis and fluorescence, IR) and also by 1H and 13C RMN methods. The photophysical properties, fluorescence and phosphorescence emission spectra, and fluorescence quantum yield of TX-Np-SO2 were determined, as well as the fluorescence lifetime (τF = 3,62 ns) and the phosphorescence lifetime (τPh = 800 ms). The transient absorption spectra of TX-Np-SO2 in degassed solutions of methanol, acetonitrile and methylcyclohexane were determined by Laser Flash Photolysis, as well as the bimolecular triplet quenching rate constants for of the derivative by various compounds. The photopolymerization of methyl methacrylate (MMA) initiated by TX-Np-SO2 was studied by dilatometry. The polymerization reaction of the initiator (TX-Np-SO2) in the presence of amine and MMA monomer was studied in order to determine the polymerization rate (Rp) at different loadings of triethylamine (TEA) and ethyl-4-dimethylaminobenzoate (EDB).

Advisors/Committee Members: Neumann, Miguel Guillermo.

Subjects/Keywords: derivado de tioxantona; fotofísica; fotoiniciador; fotopolimerização; photoinitiation; photophysics; photopolymerization; thioxanthone derivative

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Pinto, L. F. A. (2013). Preparação e caracterização fotoquímica de derivado de S,S-dioxidotioxantona: aplicações em fotopolimerização. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/75/75131/tde-24022014-114205/ ;

Chicago Manual of Style (16^th Edition):

Pinto, Leticia Felipe Abdias. “Preparação e caracterização fotoquímica de derivado de S,S-dioxidotioxantona: aplicações em fotopolimerização.” 2013. Doctoral Dissertation, University of São Paulo. Accessed September 16, 2019. http://www.teses.usp.br/teses/disponiveis/75/75131/tde-24022014-114205/ ;.

MLA Handbook (7^th Edition):

Pinto, Leticia Felipe Abdias. “Preparação e caracterização fotoquímica de derivado de S,S-dioxidotioxantona: aplicações em fotopolimerização.” 2013. Web. 16 Sep 2019.

Vancouver:

Pinto LFA. Preparação e caracterização fotoquímica de derivado de S,S-dioxidotioxantona: aplicações em fotopolimerização. [Internet] [Doctoral dissertation]. University of São Paulo; 2013. [cited 2019 Sep 16]. Available from: http://www.teses.usp.br/teses/disponiveis/75/75131/tde-24022014-114205/ ;.

Council of Science Editors:

Pinto LFA. Preparação e caracterização fotoquímica de derivado de S,S-dioxidotioxantona: aplicações em fotopolimerização. [Doctoral Dissertation]. University of São Paulo; 2013. Available from: http://www.teses.usp.br/teses/disponiveis/75/75131/tde-24022014-114205/ ;

Temple University

13. Pochas, Christopher Michael. The Effects of Vibronic Coupling on the Photophysics of Excitons and Polarons in Ordered and Disordered π-Conjugated Molecular Aggregates.

Degree: PhD, 2014, Temple University

URL: http://digital.library.temple.edu/u?/p245801coll10,323662

►

Chemistry

A theoretical model describing photophysics of π-conjugated aggregates, such as molecular crystals and polymer thin films, is developed. A Holstein-like Hamiltonian expressed with a… (more)

Subjects/Keywords: Physical chemistry;

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Pochas, C. M. (2014). The Effects of Vibronic Coupling on the Photophysics of Excitons and Polarons in Ordered and Disordered π-Conjugated Molecular Aggregates. (Doctoral Dissertation). Temple University. Retrieved from http://digital.library.temple.edu/u?/p245801coll10,323662

Chicago Manual of Style (16^th Edition):

Pochas, Christopher Michael. “The Effects of Vibronic Coupling on the Photophysics of Excitons and Polarons in Ordered and Disordered π-Conjugated Molecular Aggregates.” 2014. Doctoral Dissertation, Temple University. Accessed September 16, 2019. http://digital.library.temple.edu/u?/p245801coll10,323662.

MLA Handbook (7^th Edition):

Pochas, Christopher Michael. “The Effects of Vibronic Coupling on the Photophysics of Excitons and Polarons in Ordered and Disordered π-Conjugated Molecular Aggregates.” 2014. Web. 16 Sep 2019.

Vancouver:

Pochas CM. The Effects of Vibronic Coupling on the Photophysics of Excitons and Polarons in Ordered and Disordered π-Conjugated Molecular Aggregates. [Internet] [Doctoral dissertation]. Temple University; 2014. [cited 2019 Sep 16]. Available from: http://digital.library.temple.edu/u?/p245801coll10,323662.

Council of Science Editors:

Pochas CM. The Effects of Vibronic Coupling on the Photophysics of Excitons and Polarons in Ordered and Disordered π-Conjugated Molecular Aggregates. [Doctoral Dissertation]. Temple University; 2014. Available from: http://digital.library.temple.edu/u?/p245801coll10,323662

University of Colorado

14. Hughes, Barbara Katherine. Manipulation of Composition, Morphology, and Surface Chemistry of Semiconductor Quantum Dots for Enhanced Photophysics.

Degree: PhD, Chemistry & Biochemistry, 2013, University of Colorado

URL: http://scholar.colorado.edu/chem_gradetds/88

► Semiconductor quantum dots (QDs) are an interesting class of materials in that they exhibit unique physical properties when compared to their bulk counterparts. These… (more)

▼ Semiconductor quantum dots (QDs) are an interesting class of materials in that they exhibit unique physical properties when compared to their bulk counterparts. These unique properties and the breadth of tunability which they possess have made QD research a major field of study for more than 20 years for technologies such as catalysis, bio-imaging, solid-state lighting, and solar energy conversion. The primary concern for the application of semiconductor QDs in any field is not only to be able to precisely control physical properties (i.e., optical, electrical, magnetic) but also to understand how to achieve increased stability in these materials. A greater understanding of the chemistry of QD growth, surface construction, and composition are necessary to realize these goals. This thesis explores each of these areas of QD chemistry and the subsequent effects on their photophysical properties. Through manipulation of QD morphology, we have prepared PbSe QD dimers, which has allowed for a better understanding of electronic structure in quantum confined systems. Specifically we have observed a new absorption feature in the 1st exciton QD-dimer spectra, which we assign to a splitting of the 8-fold degenerate 1S level upon fusion of two monomer species. Surface treatment of PbSe QDs with a newly synthesized alkylselenide ligand has led to higher air stability, unique temperature dependent PL properties and the observation of a new surface-related trap level. Alongside producing more stable QDs, the nature of the strong Pb_surface to Se-R bond may also have implications for affecting kinetic processes like carrier relaxation, which could facilitate production of materials that show enhanced multiple exciton generation (MEG) yields. Finally, substitutional doping of PbSe QDs has allowed for modulation of QD compositions and in turn tuning of the dominant carrier type in both solution and in QD films. Although just a small contribution to the larger reservoir of work in this area, these results provide promise for improving stability and efficiency of QD devices for solar energy conversion. Advisors/Committee Members: Arthur J. Nozik, David M. Jonas, Garry Rumbles, Gordana Dukovic, Ivan Smalyukh.

Subjects/Keywords: morphology; photophysics; quantum dots; surface chemistry; Physical Chemistry

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Hughes, B. K. (2013). Manipulation of Composition, Morphology, and Surface Chemistry of Semiconductor Quantum Dots for Enhanced Photophysics. (Doctoral Dissertation). University of Colorado. Retrieved from http://scholar.colorado.edu/chem_gradetds/88

Chicago Manual of Style (16^th Edition):

Hughes, Barbara Katherine. “Manipulation of Composition, Morphology, and Surface Chemistry of Semiconductor Quantum Dots for Enhanced Photophysics.” 2013. Doctoral Dissertation, University of Colorado. Accessed September 16, 2019. http://scholar.colorado.edu/chem_gradetds/88.

MLA Handbook (7^th Edition):

Hughes, Barbara Katherine. “Manipulation of Composition, Morphology, and Surface Chemistry of Semiconductor Quantum Dots for Enhanced Photophysics.” 2013. Web. 16 Sep 2019.

Vancouver:

Hughes BK. Manipulation of Composition, Morphology, and Surface Chemistry of Semiconductor Quantum Dots for Enhanced Photophysics. [Internet] [Doctoral dissertation]. University of Colorado; 2013. [cited 2019 Sep 16]. Available from: http://scholar.colorado.edu/chem_gradetds/88.

Council of Science Editors:

Hughes BK. Manipulation of Composition, Morphology, and Surface Chemistry of Semiconductor Quantum Dots for Enhanced Photophysics. [Doctoral Dissertation]. University of Colorado; 2013. Available from: http://scholar.colorado.edu/chem_gradetds/88

University of Colorado

15. Donohoo-Vallett, Paul John. Control of Photophysical Processes Through Nuclear Motions — Design and Characterization.

Degree: PhD, Chemistry & Biochemistry, 2013, University of Colorado

URL: http://scholar.colorado.edu/chem_gradetds/94

► In order to achieve third-generation solar devices, the basic photophysics of light-absorbing materials must be thoroughly understood. Herein, vibrational motions are explored as potential… (more)

▼ In order to achieve third-generation solar devices, the basic photophysics of light-absorbing materials must be thoroughly understood. Herein, vibrational motions are explored as potential methods by which excited-state dynamics can be controlled. In an effort to prevent charge-recombination, vibrationally activated photoinduced dissociative electron transfer (ET) of the type [Ru^II(A)_n(L–X)] ²⁺ + hν⟶ [Ru^III(A)_n(L–X)•^–]²+*⟶ [Ru^III (A)_n(L•)]³⁺ + X^– (L = polypyridine ligand; X = halogen; A = ancillary ligand) is explored computationally and experimentally. Density functional theory (DFT) calculations employed a thermochemical cycle to determine structural and electronic factors influencing ΔE_rxn. Intramolecular strain is shown to decrease ΔE_rxn and the formation of a contact ion pair (CIP) state is determined to be a favored product. Thus, parent complex [Ru(tpy)₂]²⁺ (1) (tpy = 2,2':6',2''-terpyridine) is compared with two compounds [Ru(6,6''-Br₂-tpy)(tpy)]²⁺ (2) and [Ru(6,6''-Br₂-tpy)₂]²⁺ (3), that incorporate interligand strain. The crystal structure of 3 is distorted due to strain as compared to 1. While electronic absorption in 2 and 3 is weakened relative to transitions in 1, a strong interligand charge transfer (CT) transition is observed. Ultrafast transient absorption spectroscopy revealed coherent vibrational dynamics in 3 and 2 that were assigned to Br motion. In spite of additional strain, the excited-state lifetime of 3 is ~6x longer than 2. Constrained-DFT calculations shows the strain-induced geometric distortions in 3 causes a nesting of excited state surfaces, extending excited-state lifetime. Kinetic evidence is presented for C–Br bond scission in 3 and formation of the predicted CIP. A secondary project explores singlet fission (SF) — a process where one photon produces two excited-states. DFT calculations are used to explore a series of bistetracene (BT) molecular dimers connected by norbonyl bridges that exhibit through-space and through-bond electronic coupling. Dimer orientation and separation is shown to significantly affect SF driving force, Davydov splitting, and the magnitude of matrix elements important to CT-mediated SF. It is determined that BT1-cis, a norbonyl bridged dimer connected at the 1,2 tetracene positions with both tetracenes extending in the same direction, is most favorable for SF due to an exoergic SF driving force (–119 meV) and increased magnitudes of Davydov splitting and ET matrix elements. Advisors/Committee Members: Niels H. Damrauer, David M. Jonas, Cortland G. Pierpont, Joel Eaves, Henry Kapteyn.

Subjects/Keywords: density functional theory; electron transfer; photophysics; singlet fission; Chemistry; Physical Chemistry

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Donohoo-Vallett, P. J. (2013). Control of Photophysical Processes Through Nuclear Motions — Design and Characterization. (Doctoral Dissertation). University of Colorado. Retrieved from http://scholar.colorado.edu/chem_gradetds/94

Chicago Manual of Style (16^th Edition):

Donohoo-Vallett, Paul John. “Control of Photophysical Processes Through Nuclear Motions — Design and Characterization.” 2013. Doctoral Dissertation, University of Colorado. Accessed September 16, 2019. http://scholar.colorado.edu/chem_gradetds/94.

MLA Handbook (7^th Edition):

Donohoo-Vallett, Paul John. “Control of Photophysical Processes Through Nuclear Motions — Design and Characterization.” 2013. Web. 16 Sep 2019.

Vancouver:

Donohoo-Vallett PJ. Control of Photophysical Processes Through Nuclear Motions — Design and Characterization. [Internet] [Doctoral dissertation]. University of Colorado; 2013. [cited 2019 Sep 16]. Available from: http://scholar.colorado.edu/chem_gradetds/94.

Council of Science Editors:

Donohoo-Vallett PJ. Control of Photophysical Processes Through Nuclear Motions — Design and Characterization. [Doctoral Dissertation]. University of Colorado; 2013. Available from: http://scholar.colorado.edu/chem_gradetds/94

University of Colorado

16. Schnitzenbaumer, Kyle J. The Impact of Chalcogenide Ligands on the Photoexcited States of Cadmium Chalcogenide Quantum Dots.

Degree: PhD, Chemistry & Biochemistry, 2015, University of Colorado

URL: http://scholar.colorado.edu/chem_gradetds/159

► Quantum dots (QDs) are the foundation of many optoelectronic devices because their optical and electronic properties are synthetically tunable. The inherent connection between synthetically… (more)

Subjects/Keywords: Chalcogenide Ligands; Photophysics; Quantum Dots; Transient Absorption Spectroscopy; Physical Chemistry

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APA (6^th Edition):

Schnitzenbaumer, K. J. (2015). The Impact of Chalcogenide Ligands on the Photoexcited States of Cadmium Chalcogenide Quantum Dots. (Doctoral Dissertation). University of Colorado. Retrieved from http://scholar.colorado.edu/chem_gradetds/159

Chicago Manual of Style (16^th Edition):

Schnitzenbaumer, Kyle J. “The Impact of Chalcogenide Ligands on the Photoexcited States of Cadmium Chalcogenide Quantum Dots.” 2015. Doctoral Dissertation, University of Colorado. Accessed September 16, 2019. http://scholar.colorado.edu/chem_gradetds/159.

MLA Handbook (7^th Edition):

Schnitzenbaumer, Kyle J. “The Impact of Chalcogenide Ligands on the Photoexcited States of Cadmium Chalcogenide Quantum Dots.” 2015. Web. 16 Sep 2019.

Vancouver:

Schnitzenbaumer KJ. The Impact of Chalcogenide Ligands on the Photoexcited States of Cadmium Chalcogenide Quantum Dots. [Internet] [Doctoral dissertation]. University of Colorado; 2015. [cited 2019 Sep 16]. Available from: http://scholar.colorado.edu/chem_gradetds/159.

Council of Science Editors:

Schnitzenbaumer KJ. The Impact of Chalcogenide Ligands on the Photoexcited States of Cadmium Chalcogenide Quantum Dots. [Doctoral Dissertation]. University of Colorado; 2015. Available from: http://scholar.colorado.edu/chem_gradetds/159

Univerzitet u Beogradu

17. Petrović, Jovana, 1978-. Анализа фотогенерације и рекомбинације носилаца наелектрисања у проводним полимерима са применом на фотодетекторе.

Degree: Elektrotehnički fakultet, 2013, Univerzitet u Beogradu

URL: https://fedorabg.bg.ac.rs/fedora/get/o:5486/bdef:Content/get

Optoelektronika - Polimerski fotodetektori / Optoelectronics - Polymer photodetectors Advisors/Committee Members: Matavulj, Petar, 1971-.

Subjects/Keywords: condyctive polymers; photophysics; photodetector

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APA (6^th Edition):

Petrović, Jovana, 1. (2013). Анализа фотогенерације и рекомбинације носилаца наелектрисања у проводним полимерима са применом на фотодетекторе. (Thesis). Univerzitet u Beogradu. Retrieved from https://fedorabg.bg.ac.rs/fedora/get/o:5486/bdef:Content/get

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Petrović, Jovana, 1978-. “Анализа фотогенерације и рекомбинације носилаца наелектрисања у проводним полимерима са применом на фотодетекторе.” 2013. Thesis, Univerzitet u Beogradu. Accessed September 16, 2019. https://fedorabg.bg.ac.rs/fedora/get/o:5486/bdef:Content/get.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Petrović, Jovana, 1978-. “Анализа фотогенерације и рекомбинације носилаца наелектрисања у проводним полимерима са применом на фотодетекторе.” 2013. Web. 16 Sep 2019.

Vancouver:

Petrović, Jovana 1. Анализа фотогенерације и рекомбинације носилаца наелектрисања у проводним полимерима са применом на фотодетекторе. [Internet] [Thesis]. Univerzitet u Beogradu; 2013. [cited 2019 Sep 16]. Available from: https://fedorabg.bg.ac.rs/fedora/get/o:5486/bdef:Content/get.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Petrović, Jovana 1. Анализа фотогенерације и рекомбинације носилаца наелектрисања у проводним полимерима са применом на фотодетекторе. [Thesis]. Univerzitet u Beogradu; 2013. Available from: https://fedorabg.bg.ac.rs/fedora/get/o:5486/bdef:Content/get

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

The Ohio State University

18. Hare, Patrick Michael. Excuted state dynamics in DNA base monomers: the effects of solvent and chemical modification in ultrafast internal conversion.

Degree: PhD, Chemistry, 2007, The Ohio State University

URL: http://rave.ohiolink.edu/etdc/view?acc_num=osu1166623261

► The excited state dynamics of four of the five naturally occurring nucleic acid bases and several of their derivatives were studied by femtosecond transient absorption… (more)

▼ The excited state dynamics of four of the five naturally occurring nucleic acid bases and several of their derivatives were studied by femtosecond transient absorption spectroscopy. Two tautomers of Adenine were distinguished in solution, with the canonical 9H tautomer having a 1pipi* lifetime of ~200 fs. The 7H tautomer, that we determined accounts for 22 +/- 4% of the population, has a forty-fold longer lifetime. The 1pipi* lifetimes of 1-, 3-, and 9-methyladenine were found to be the same as the 9H tautomer. The lifetime of 7-methyladenine was ~4 ps, half the lifetime of the 7H tautomer. Neither the lifetimes nor the relative populations of the tautomers changed drastically with solvent. The effects of protonation on the excited state lifetimes were also studied. These results were interpreted in light of several proposals for the excited state decay mechanism. A new intermediate state between the excited 1pipi* state and the ground state was observed to be specific to the pyrimidine bases uracil, thymine, cytosine and their derivatives. This state, assigned to the lowest energy 1npi* state, absorbs between ~300 and 450 nm and displays a lifetime that is sensitive to solvent and varies strongly between pyrimidines, with the lifetime much longer in the nucleotides than in the bases. UV probe experiments showed that 50 to 90% of the excited population decays via direct internal conversion to the ground state. The remaining 10 – 50% ends up in the 1npi* state where it either decays directly to the ground state or intersystem crosses to the triplet state. The triplet yield for 1-cyclohexyluracil was measured as a function of solvent. The triplet yield was found to increase as the solvent hydrogen bond donating ability decreased. Triplet state formation was observed to be complete within ~10 ps. These observations in the pyrimidines lead to a new picture of the excited state dynamics of these molecules in solution. Advisors/Committee Members: Kohler, Bern (Advisor).

Subjects/Keywords: Chemistry, Physical; nucleic acids; photophysics; transient absorption; ultrafast spectroscopy

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APA (6^th Edition):

Hare, P. M. (2007). Excuted state dynamics in DNA base monomers: the effects of solvent and chemical modification in ultrafast internal conversion. (Doctoral Dissertation). The Ohio State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=osu1166623261

Chicago Manual of Style (16^th Edition):

Hare, Patrick Michael. “Excuted state dynamics in DNA base monomers: the effects of solvent and chemical modification in ultrafast internal conversion.” 2007. Doctoral Dissertation, The Ohio State University. Accessed September 16, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1166623261.

MLA Handbook (7^th Edition):

Hare, Patrick Michael. “Excuted state dynamics in DNA base monomers: the effects of solvent and chemical modification in ultrafast internal conversion.” 2007. Web. 16 Sep 2019.

Vancouver:

Hare PM. Excuted state dynamics in DNA base monomers: the effects of solvent and chemical modification in ultrafast internal conversion. [Internet] [Doctoral dissertation]. The Ohio State University; 2007. [cited 2019 Sep 16]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1166623261.

Council of Science Editors:

Hare PM. Excuted state dynamics in DNA base monomers: the effects of solvent and chemical modification in ultrafast internal conversion. [Doctoral Dissertation]. The Ohio State University; 2007. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1166623261

Dublin City University

19. Finn, Stephen. Ruthenium polypyridyl complexes with long aliphatic chains; photophysics, interfacial assembly and cell imaging.

Degree: School of Chemical Sciences, 2011, Dublin City University

URL: http://doras.dcu.ie/16611/

► A series of novel Ruthenium polypyridyl complexes [Ru(dpp)2(x-ATAP)](PF6)2 were synthesised and their photophysical and electrochemical properties are reported on, where x-ATAP is either 5-Amido-1,10-phenanthroline-(6-acetylthio-hexanyl), 5-Amido-1,10-phenanthroline-(8-acetylthio-octanyl),… (more)

▼ A series of novel Ruthenium polypyridyl complexes [Ru(dpp)2(x-ATAP)](PF6)2 were synthesised and their photophysical and electrochemical properties are reported on, where x-ATAP is either 5-Amido-1,10-phenanthroline-(6-acetylthio-hexanyl), 5-Amido-1,10-phenanthroline-(8-acetylthio-octanyl), 5-Amido-1,10-phenanthroline-(11-acetylthio-undecanyl) or 5-Amido-1,10-phenanthroline-(16-acetylthio-hexadecanyl). These complexes exhibit bright emission. They are capable of self assembly on metallic surfaces. Furthermore, this series of complexes are capable of forming bilayer vesicle structures in aqueous conditions. Chapter 3 describes the synthesis, photophysics and solution phase electrochemistry of these complexes. The solvent dependence of the luminescence properties is also addressed along with the formation of bilayer vesicles of these compounds in aqueous conditions. In chapter 4 self assembled monolayers of the Ru(dpp)2(x-ATAP)](PF6)2 complexes were formed on platinum electrodes and these monolayers were characterized electrochemically. These monolayers were found to be somewhat unstable when analysed electrochemically even when backfilled with an appropriate length alkanethiol. Attempts to study the distance dependence of electron transfer reveal that these complexes when functionalized on metal surfaces lie flat on the surface as opposed to the ruthenium headgroup being raised above the surface. The photophysical properties of these monolayers on gold and platinum electrodes and gold nanoparticles are also reported. Despite the close proximity of the headgroup to the metal surface the monolayers remain luminescent and exhibit large SERS enhancement when absorbed on aggregated gold nanoparticle clusters. Chapter 5 explores the interactions of the Ru(dpp)2(x-ATAP)](PF6)2 complexes with monoclonal cells and their suitability as luminescence cell imaging probes. A CHO cell line (Chinese hamster ovary cell) were stained with the Ru(dpp)2(x-ATAP)](PF6)2. This series of complexes was capable of crossing the cell membrane barrier and localizing in discrete compartments of the cell. The stained cell line was imaged by FLIM (fluorescence lifetime imaging microscopy) and 3D z-stacked images of the cell were constructed. It was found that there was an alkyl chain length dependence on the localization of these complexes within the cell. Complexes with short alkyl chains stained throughout the cytoplasm and nucleus while the complexes with longer alkyl chains remain localized in endosomes. Finally chapter 6 explores a novel ruthenium(II) bis-terpyridyl type complex, [RuII(LKet)2].(PF6)2. This complex was characterized photophysically and electrochemically. By extending the structure of the 2,2';6',2"-terpyridine (tpy) ligands with carbonyl bridging units the ruthenium the [RuII(LKet)2].(PF6)2 complex cage structure is much closer to perfect octahedral configuration compared to [RuII(tpy)2]2+. The photophysical performance in ambient conditions of [RuII(LKet)2].(PF6)2 is massively increased compared to [RuII(tpy)2]2+ or… Advisors/Committee Members: Keyes, Tia E., Forster, Robert J., IRCSET, HEA.

Subjects/Keywords: Chemistry; Ruthenium; Cell Imaging; Interfacial Assembly; Supramolecular Chemistry; Photophysics

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APA (6^th Edition):

Finn, S. (2011). Ruthenium polypyridyl complexes with long aliphatic chains; photophysics, interfacial assembly and cell imaging. (Thesis). Dublin City University. Retrieved from http://doras.dcu.ie/16611/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Finn, Stephen. “Ruthenium polypyridyl complexes with long aliphatic chains; photophysics, interfacial assembly and cell imaging.” 2011. Thesis, Dublin City University. Accessed September 16, 2019. http://doras.dcu.ie/16611/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Finn, Stephen. “Ruthenium polypyridyl complexes with long aliphatic chains; photophysics, interfacial assembly and cell imaging.” 2011. Web. 16 Sep 2019.

Vancouver:

Finn S. Ruthenium polypyridyl complexes with long aliphatic chains; photophysics, interfacial assembly and cell imaging. [Internet] [Thesis]. Dublin City University; 2011. [cited 2019 Sep 16]. Available from: http://doras.dcu.ie/16611/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Finn S. Ruthenium polypyridyl complexes with long aliphatic chains; photophysics, interfacial assembly and cell imaging. [Thesis]. Dublin City University; 2011. Available from: http://doras.dcu.ie/16611/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Bowling Green State University

20. Montes, Victor A. Synthesis and Electro-optical Properties of Novel Materials for Application in Organic Light-Emitting Diodes.

Degree: PhD, Photochemical Sciences, 2007, Bowling Green State University

URL: http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1173835623

► Organic light-emitting diodes (OLEDs) could become the leading lighting technology for fabrication of full color flat panel displays and general illumination purposes in the… (more)

▼ Organic light-emitting diodes (OLEDs) could become the leading lighting technology for fabrication of full color flat panel displays and general illumination purposes in the near future. To meet this goal, operational hurdles still need to be addressed in electroluminescent devices. In particular, long-term operation and efficient performance are the main challenges to be tackled. Energy transfer processes play a significant role in the improvement of electroluminescence efficiency by utilizing all of the excited states generated during the electron-hole recombination, in particular non-emissive triplet excitons. In this regard, the advantageous energy transfer features displayed by molecular photonic wires could be of practical importance for the fabrication of efficient OLEDs. In the present work, donor-bridge-acceptor triads with appropriate triplet energy alignment of the components were studied. The systems consisted of materials already successfully used in OLEDs. Specifically, aluminum (III) tris(8-quinolinolate) was used as a triplet energy donor (³Alq₃ = 2.17 eV), fluorene oligomers as the connecting bridge (³OF_1-4 = 2.86-2.18 eV), and platinum (II) tetraphenylporphyrin as an energy acceptor (³PtTPP = 1.91 eV). The molecular photonic wire behavior of these triads was investigated and OLEDs were fabricated. A rationale for tuning the excited-state energies of Alq₃was introduced. The synthetic preparation of tunable derivatives bearing conjugated aryl spacers was realized. Red, green, and blue electroluminescence was obtained from OLEDs fabricated using the Alq₃-based materials. Dyad systems Alq₃-oligofluorene (n=1-9) were synthesized. Strong electronic coupling was observed for materials comprising short oligofluorene fragments (n=1, 3). These systems were used as components for the construction of triads to study molecular photonic wire behavior. Donor-bridge-acceptor triads with a small number of fluorene units (n=1-4) were prepared. In these systems efficient singlet and triplet energy transfer were observed. Furthermore, improved OLED output was obtained for triads having longer oligofluorene bridges showing better alignment of triplet energy levels despite the longer donor-acceptor distance. This constitutes the first example of molecular photonic wire behavior demonstrated to take place in both solid state and in functional OLEDs. Advisors/Committee Members: Anzenbacher, Pavel (Advisor).

Subjects/Keywords: Organic Electronics; OLEDs; electroluminescence; photophysics; energy transfer; molecular wire

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APA (6^th Edition):

Montes, V. A. (2007). Synthesis and Electro-optical Properties of Novel Materials for Application in Organic Light-Emitting Diodes. (Doctoral Dissertation). Bowling Green State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1173835623

Chicago Manual of Style (16^th Edition):

Montes, Victor A. “Synthesis and Electro-optical Properties of Novel Materials for Application in Organic Light-Emitting Diodes.” 2007. Doctoral Dissertation, Bowling Green State University. Accessed September 16, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1173835623.

MLA Handbook (7^th Edition):

Montes, Victor A. “Synthesis and Electro-optical Properties of Novel Materials for Application in Organic Light-Emitting Diodes.” 2007. Web. 16 Sep 2019.

Vancouver:

Montes VA. Synthesis and Electro-optical Properties of Novel Materials for Application in Organic Light-Emitting Diodes. [Internet] [Doctoral dissertation]. Bowling Green State University; 2007. [cited 2019 Sep 16]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1173835623.

Council of Science Editors:

Montes VA. Synthesis and Electro-optical Properties of Novel Materials for Application in Organic Light-Emitting Diodes. [Doctoral Dissertation]. Bowling Green State University; 2007. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1173835623

Case Western Reserve University

21. Payton, John L., PhD. The Photophysical Behavior of Aryl-diphosphenes and Aryl-phosphaalkenes: A Theoretical Study.

Degree: PhD, Chemistry, 2010, Case Western Reserve University

URL: http://rave.ohiolink.edu/etdc/view?acc_num=case1270488297

► The past several decades have seen heightened interest in molecular devices such as molecular switches, organic light emitting diodes (OLED's), molecular wires, and numerous… (more)

▼ The past several decades have seen heightened interest in molecular devices such as molecular switches, organic light emitting diodes (OLED's), molecular wires, and numerous other molecularly engineered devices. Many of these devices are organic-based materials that exploit E-Z isomerization of carbon-carbon, nitrogen-nitrogen, and/or carbon-nitrogen double bonds. As intriguing as the current literature is on these compounds, the possibility of substituting heavier main group elements, such as phosphorus, into these potentially useful systems has not been much explored. Heavier atoms may introduce new properties that currently are not available with the lighter atom cousins. High-level computational methods, including time-dependent density functional theory (TD-DFT) and complete active space ab initio methods with (CASPT2) and without (CASSCF) perturbation theory, have been used to study the E-Z isomerization of aryl-diphosphenes (Ar-P=P-Ar) and aryl-phosphaalkenes (Ar-P=C(H)-Ar). Both the thermal and photo-excited processes (energies, geometries, transitions) have been explored for three proposed isomerization pathways. The pathways examined include (1) rotation about the central double bond (C-P=E-C, E = P or C(H)), (2) in-the-plane inversion about the E=P-C bond angle, and (3) dissociation of the phosphorus-phosphorus and phosphorus-carbon double bonds for diphosphenes and phosphaalkenes, respectively. In both, diphosphenes and phosphaalkenes, rotation dominates as the preferred thermal (ground state) pathway. The calculations are also consistent with rotation as the primary mechanism for photo-induced isomerization by excitation to the low-lying electronic states. The photoisomerization of diphosphenes shows strong similarities to recently proposed models of the analogous process in azobenzene; namely, it involves a doubly excited phantom state. In contrast, phosphaalkenes parallel stilbene’s classic rotation photoisomerization pathway. These results provide invaluable insight for synthetic chemists who are attempting to understand, design, and fabricate photoactive polymeric materials. Advisors/Committee Members: Dunbar, Robert C. (Committee Chair), Protasiewicz, John D. (Advisor).

Subjects/Keywords: Chemistry; Physics; diphosphenes phosphaalkenes photochemistry photophysics photoisomerization CASPT2 TD-DFT

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Payton, John L., P. (2010). The Photophysical Behavior of Aryl-diphosphenes and Aryl-phosphaalkenes: A Theoretical Study. (Doctoral Dissertation). Case Western Reserve University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=case1270488297

Chicago Manual of Style (16^th Edition):

Payton, John L., PhD. “The Photophysical Behavior of Aryl-diphosphenes and Aryl-phosphaalkenes: A Theoretical Study.” 2010. Doctoral Dissertation, Case Western Reserve University. Accessed September 16, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=case1270488297.

MLA Handbook (7^th Edition):

Payton, John L., PhD. “The Photophysical Behavior of Aryl-diphosphenes and Aryl-phosphaalkenes: A Theoretical Study.” 2010. Web. 16 Sep 2019.

Vancouver:

Payton, John L. P. The Photophysical Behavior of Aryl-diphosphenes and Aryl-phosphaalkenes: A Theoretical Study. [Internet] [Doctoral dissertation]. Case Western Reserve University; 2010. [cited 2019 Sep 16]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=case1270488297.

Council of Science Editors:

Payton, John L. P. The Photophysical Behavior of Aryl-diphosphenes and Aryl-phosphaalkenes: A Theoretical Study. [Doctoral Dissertation]. Case Western Reserve University; 2010. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=case1270488297

University of California – Merced

22. Zeng, Youhong. Photophysics and Photochemistry of Ⅱ-Ⅵ Semiconductor Nanocrystals.

Degree: Chemistry and Chemical Biology, 2017, University of California – Merced

URL: http://www.escholarship.org/uc/item/7mx9g318

► Colloidally synthesized, 0D semiconductor nanocrystals, also referred to as Quantum Dots (QDs), are promising light-harvesting materials which have found increasing use in photovoltaic devices, LEDs… (more)

▼ Colloidally synthesized, 0D semiconductor nanocrystals, also referred to as Quantum Dots (QDs), are promising light-harvesting materials which have found increasing use in photovoltaic devices, LEDs and other optoelectronic devices. In the past two decades, they have been extensively studied in terms of their photophysical and photochemical properties. One of the most prominent features of this class of material is their size tunable optical properties, which can be explained by the quantum size effect, whereby the bandgap of a semiconductor is pushed to a larger value as the exciton experiences increased confinement. In the strong confinement regime, the degeneracy of the hole states gives rise to the fine structure of the band-edge exciton, which helps explain their unusually long radiative lifetimes (~1μs at 10 K) relative to the bulk exciton recombination time (1ns), detailed in Chapter 1. In Chapter 2, the size dependence of the radiative lifetimes of CdSe quantum dots is illustrated and compared to the calculated results using the Einstein coefficients. The quantum yield of CdSe particles is strongly related to the ratio of radiative and nonradiative recombination processes. This affects the size dependence of radiative lifetimes, and is the reason for a large discrepancy in the literature. In this section, we compare the results obtained for particles synthesized using a standard method and those obtained from an optimized synthesis. To correctly calculate the radiative lifetime of CdSe particles, it is found that three factors need to be considered: size-dependent integrated extinction coefficient, the bandedge frequency and the Boltzmann fraction of population of dark versus bright states within the lowest energy exciton fine structure. In Chapter 3, the mechanism of two-photon darkening is elucidated. When the CdSe particles are subjected to high power density irradiation, they demonstrate a prompt photoluminescence depletion, followed by a recovery in polar solvents, on the time scale of tens of minutes. The mechanism proposed is that a significant fraction of biexcitons is generated under intense irradiation, which can then undergo fast Auger recombination by transferring the recombination energy of the exciton to the remaining hole and excite it higher into the valence band. The excited hole can either relax back to the top of the valence band or tunnel out to the surface and ionize a ligand, specifically, trioctylphosphine. In the latter case, the ionization forms QD-/TOP+, which has a certain probability to dissociate into QD- and TOP+. The resulting QD- is dark, because it is negatively charged and unligated, which is attributed to the prompt photoluminescence (PL) depletion. The depletion of PL is reversible, when certain passivating ligands are present in solution, and indeed it is the charge neutralization and ligand reattachment/reorganization that determines the time scale of the PL recovery. The details are given in Chapter 3. In Chapter 4, we provide an examination of the excited hole…

Subjects/Keywords: Physical chemistry; Nanoscience; Chemistry; nanocrystals; photochemistry; photophysics; quantum dots; semiconductor

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APA (6^th Edition):

Zeng, Y. (2017). Photophysics and Photochemistry of Ⅱ-Ⅵ Semiconductor Nanocrystals. (Thesis). University of California – Merced. Retrieved from http://www.escholarship.org/uc/item/7mx9g318

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zeng, Youhong. “Photophysics and Photochemistry of Ⅱ-Ⅵ Semiconductor Nanocrystals.” 2017. Thesis, University of California – Merced. Accessed September 16, 2019. http://www.escholarship.org/uc/item/7mx9g318.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zeng, Youhong. “Photophysics and Photochemistry of Ⅱ-Ⅵ Semiconductor Nanocrystals.” 2017. Web. 16 Sep 2019.

Vancouver:

Zeng Y. Photophysics and Photochemistry of Ⅱ-Ⅵ Semiconductor Nanocrystals. [Internet] [Thesis]. University of California – Merced; 2017. [cited 2019 Sep 16]. Available from: http://www.escholarship.org/uc/item/7mx9g318.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zeng Y. Photophysics and Photochemistry of Ⅱ-Ⅵ Semiconductor Nanocrystals. [Thesis]. University of California – Merced; 2017. Available from: http://www.escholarship.org/uc/item/7mx9g318

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Virginia Tech

23. Rowe, Jennifer Maria. Design and Synthesis of Photoactive Metal-Organic Frameworks for Photon Upconversion and Energy Transfer Studies.

Degree: PhD, Chemistry, 2018, Virginia Tech

URL: http://hdl.handle.net/10919/83875

► The synthesis, characterization and photophysical properties of three Zr-based Metalorganic frameworks (MOFs) assembled from 2,6-anthracenedicarboxylic acid (2,6-ADCA, 2,6- MOF) and 1,4-anthracenedicarboxylic (1,4-ADCA, 1,4-MOF), and 9,10-anthracenedicarboxylic… (more)

▼ The synthesis, characterization and photophysical properties of three Zr-based Metalorganic frameworks (MOFs) assembled from 2,6-anthracenedicarboxylic acid (2,6-ADCA, 2,6- MOF) and 1,4-anthracenedicarboxylic (1,4-ADCA, 1,4-MOF), and 9,10-anthracenedicarboxylic acid (9,10-ADCA, 9,10-MOF) are described. The crystal structure of the 9,10-MOF was elucidated by synchrotron powder X-ray diffraction (PXRD) analysis and is isostructural with the well-known UiO-66 framework. The 2,6-MOFs also form highly crystalline, octahedral-shaped structures and was characterized by PXRD. Le Bail refinement of the powder pattern revealed that the 2,6-MOF also has UiO-type crystal structure. Conversely, incorporation of the 1,4-ADCA ligand results in large rod-shaped crystals. The excited-state properties of the MOFs were examined using steadstate diffuse reflectance, steady-state emission spectroscopy and time-correlated single photon counting (TCSPC) spectroscopy and are compared to those of the corresponding ligand in solution. Both the unique fluorescent properties of the ligand as well as individual framework structure, result in distinctive luminescent behavior and dictate the extent of intermolecular interactions. Specifically, the 2,6-MOF displays monomeric emission with a fluorescence lifetime (t) of 16.6 ± 1.1 and fluorescence quantum yield (Ff). On the other hand, the 1,4-MOF displays both monomeric and excimeric emission, with corresponding lifetime values of 7.5 ± 0.01 and 19.9 ± 0.1, respectively and a quantum yield of 0.002 ± 0.0001. The propensity for photon upconversion through sensitized triplet-triplet annihilation (TTA-UC) was probed in the three anthracene-based MOFs. The MOFs were surface-modified with Pd(II) mesoporphyrin IX (PdMP) as the triplet sensitizer. Upconverted emission from the 9,10-MOF was observed, with a quantum efficiency (FUC) of 0.46 % and a threshold intensity (Ith) of 142 mW/cm2 . The variation of the spacing between the anthracene units in the MOFs was found to have significant impact on TTA-UC. As a result, upconverted emission is only displayed by the 9-10-MOF. The distance between anthracene linkers in the 2,6-MOF are too large for TTA to occur, while the short distances in the 1,4-MOF inhibit upconversion through competitive excimer formation. To further explore the effects of chromophore spacing on energy transfer processes, a series of zinc-based mixed-ligand MOF were constructed from Zn(II) tetrakis(4- carboxyphenyl)porphyrin (ZnTCPP) and pyrazine, 2,2′-bipyridine (pyz) or 4,4′-bipyridyl (bpy) or 1,4-di(4-pyridyl)benzense (dpbz), comprising ZnTCPP/Zn paddlewheel layers. Across this series, the porphyrin spacing was approximately 6 Å, 11 Å and 16 Å for pyz, bpy and dpbz, respectively. The photophysical properties of the MOFs were explored using stead-state diffuse reflectance spectroscopy and steady-state and time-resolved emission spectroscopies. Florescence quenching studies examined the correlation between porphyrin spacing and efficiency of energy transfer. Advisors/Committee Members: Morris, Amanda (committeechair), Tissue, Brian M. (committee member), Morris, John R. (committee member), Tanko, James M. (committee member).

Subjects/Keywords: Metal-Organic Frameworks; Photophysics; Photon Upconversion; Energy Transfer

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APA (6^th Edition):

Rowe, J. M. (2018). Design and Synthesis of Photoactive Metal-Organic Frameworks for Photon Upconversion and Energy Transfer Studies. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/83875

Chicago Manual of Style (16^th Edition):

Rowe, Jennifer Maria. “Design and Synthesis of Photoactive Metal-Organic Frameworks for Photon Upconversion and Energy Transfer Studies.” 2018. Doctoral Dissertation, Virginia Tech. Accessed September 16, 2019. http://hdl.handle.net/10919/83875.

MLA Handbook (7^th Edition):

Rowe, Jennifer Maria. “Design and Synthesis of Photoactive Metal-Organic Frameworks for Photon Upconversion and Energy Transfer Studies.” 2018. Web. 16 Sep 2019.

Vancouver:

Rowe JM. Design and Synthesis of Photoactive Metal-Organic Frameworks for Photon Upconversion and Energy Transfer Studies. [Internet] [Doctoral dissertation]. Virginia Tech; 2018. [cited 2019 Sep 16]. Available from: http://hdl.handle.net/10919/83875.

Council of Science Editors:

Rowe JM. Design and Synthesis of Photoactive Metal-Organic Frameworks for Photon Upconversion and Energy Transfer Studies. [Doctoral Dissertation]. Virginia Tech; 2018. Available from: http://hdl.handle.net/10919/83875

University of St. Andrews

24. Hedley, Gordon J. Ultrafast photophysics of iridium complexes .

Degree: 2010, University of St. Andrews

URL: http://hdl.handle.net/10023/1981

► This thesis presents ultrafast photophysical measurements on a number of phosphorescent iridium complexes and establishes relationships between the relaxation rates and the vibrational properties of… (more)

▼ This thesis presents ultrafast photophysical measurements on a number of phosphorescent iridium complexes and establishes relationships between the relaxation rates and the vibrational properties of the material. When ultrafast luminescence is measured on the peak of the phosphorescence spectrum and on its red-side, 230 fs and 3 ps decay time constants were observed in all materials studied, and this was attributed to population redistribution amongst the three electronic substates of the lowest triplet metal-ligand charge transfer (MLCT) state. The observation of luminescence at higher values of energy embodied ultrafast dissipation of excess energy by intramolecular vibrational redistribution (IVR) and it was found that the dissipation channels and rate of IVR could be modified by chemical modification of the emitting molecule. This was tested in two ways. Firstly by adding electronically inactive dendrons to the core, an increase in the preference for dissipation of excess energy by IVR rather than by picosecond cooling to the solvent molecules was found, but this did not change the rate of IVR. The second method of testing was by fusing a phenyl moiety directly onto the ligand, this both increased the rate of IVR and also the preference for dissipation by it rather than by picosecond cooling. Fluorescence was recorded in an iridium complex for the first time and a decay time constant of 65 fs was found, thus allowing a direct observation of intersystem crossing (ISC) to be made. In a deep red emitting iridium complex internal conversion (IC) and ISC were observed and the factors controlling their time constants deduced. IC was found to occur by dissipation of excess energy by IVR. The rate of IC was found to be dependent on the amount of vibrational energy stored in the molecule, with IC fast (< 45 fs) when < 0.6 eV of energy is stored and slower (~ 70 fs) when the value is > 0.6 eV. The rate of ISC agreed with these findings, indicating that the very process of ISC may be thought of as closely analogous to that of IC given the strongly spin-mixed nature of the singlet and triplet MLCT states. Advisors/Committee Members: Samuel, Ifor D. W (advisor).

Subjects/Keywords: Ultrafast; Photophysics; Chemical physics; Transition metal complex; Iridium; Phosphorescence

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APA (6^th Edition):

Hedley, G. J. (2010). Ultrafast photophysics of iridium complexes . (Thesis). University of St. Andrews. Retrieved from http://hdl.handle.net/10023/1981

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Hedley, Gordon J. “Ultrafast photophysics of iridium complexes .” 2010. Thesis, University of St. Andrews. Accessed September 16, 2019. http://hdl.handle.net/10023/1981.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Hedley, Gordon J. “Ultrafast photophysics of iridium complexes .” 2010. Web. 16 Sep 2019.

Vancouver:

Hedley GJ. Ultrafast photophysics of iridium complexes . [Internet] [Thesis]. University of St. Andrews; 2010. [cited 2019 Sep 16]. Available from: http://hdl.handle.net/10023/1981.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Hedley GJ. Ultrafast photophysics of iridium complexes . [Thesis]. University of St. Andrews; 2010. Available from: http://hdl.handle.net/10023/1981

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Oxford

25. Movsisyan, Levon. Polyyne rotaxanes.

Degree: PhD, 2014, University of Oxford

URL: http://ora.ox.ac.uk/objects/uuid:7f436a99-071f-4cc5-a4b5-5779e1aa3347 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.640047

► This thesis describes the synthesis of polyyne rotaxanes and an investigation of their excited state photophysical properties. The threading of dumbbell-shaped carbon chains with macrocyclic… (more)

▼ This thesis describes the synthesis of polyyne rotaxanes and an investigation of their excited state photophysical properties. The threading of dumbbell-shaped carbon chains with macrocyclic components is a way to mechanically insulate and control the environment around the carbon chains. The resulting polyyne rotaxanes can serve as model compounds for insulated carbyne. Different strategies have been tested for the synthesis of polyyne rotaxanes with different topologies and structures. Study of rotaxanes in the excited states reveals strong electronic communication between an acetylenic thread and a macrocycle. Chapter 1 summarizes the field of acetylene scaffolding, introducing some recent achievements in acetylene chemistry. General synthetic methods for polyynes are discussed, and an introduction to active metal template synthesis of rotaxanes is given. Chapter 2 describes the synthesis of a family of polyyne rotaxanes with different axle lengths and macrocycles, prepared by homocoupling of terminal alkynes. Synthesis of hexayne rotaxane with functional pyridine end-group is presented and a number of crystal structures of polyyne rotaxanes are analyzed. Chapter 3 demonstrates the use of acetylene cross-coupling in the synthesis of rotaxanes. Synthesis of rotaxanes with different topological structure is provided. Chapter 4 details the excited state properties of polyynes studied by time -resolved spectroscopy. The complexes of rhenium(I) carbonyls with rotaxanes is presented and the excited state energy transfer in rotaxanes is studied. Chapter 5 explores new synthetic strategies for polyyne rotaxanes, using "masked" precursors. It also highlights the potential of carbenoid rearrangement of alkyliden es for the construction of linear and cyclic architectures. Chapter 6 is the summary of the project and general discussion of future directions. There are two appendices in the end of thesis: Appendix A covers the photophysics of rhenium tricarbonyl complex of the hexayne rotaxane with a small macrocycle and Appendix B reports work towards the synthesis of rotaxanes with platinum(II)-alkyne complexes.

Subjects/Keywords: 547; Organic chemistry; Polyynes; rotaxanes; Photophysics; Time-resolved spectroscopy

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APA (6^th Edition):

Movsisyan, L. (2014). Polyyne rotaxanes. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:7f436a99-071f-4cc5-a4b5-5779e1aa3347 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.640047

Chicago Manual of Style (16^th Edition):

Movsisyan, Levon. “Polyyne rotaxanes.” 2014. Doctoral Dissertation, University of Oxford. Accessed September 16, 2019. http://ora.ox.ac.uk/objects/uuid:7f436a99-071f-4cc5-a4b5-5779e1aa3347 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.640047.

MLA Handbook (7^th Edition):

Movsisyan, Levon. “Polyyne rotaxanes.” 2014. Web. 16 Sep 2019.

Vancouver:

Movsisyan L. Polyyne rotaxanes. [Internet] [Doctoral dissertation]. University of Oxford; 2014. [cited 2019 Sep 16]. Available from: http://ora.ox.ac.uk/objects/uuid:7f436a99-071f-4cc5-a4b5-5779e1aa3347 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.640047.

Council of Science Editors:

Movsisyan L. Polyyne rotaxanes. [Doctoral Dissertation]. University of Oxford; 2014. Available from: http://ora.ox.ac.uk/objects/uuid:7f436a99-071f-4cc5-a4b5-5779e1aa3347 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.640047

26. Petrović Jovana. The analysis of the charge carrier photogeneration and recombination in conductive polymers: Photodetector applications.

Degree: PhD, Electrical Engineering, 2012, University of Belgrade

URL: http://dx.doi.org/10.2298/BG20120620PETROVIC ; http://eteze.bg.ac.rs/application/showtheses?thesesId=226 ; https://fedorabg.bg.ac.rs/fedora/get/o:5486/bdef:Content/get ; http://vbs.rs/scripts/cobiss?command=SEARCH&base=99999&select=ID=43463439

►

Due to their numerous advantages over the classical semiconductors conductive polymers are among the most promising materials for modern optoelectronic applications. In order to fully… (more)

▼

Due to their numerous advantages over the classical semiconductors conductive polymers are among the most promising materials for modern optoelectronic applications. In order to fully exploit their potential it is of the greatest interest to elucidate the diverse and complex physical processes which occur in these materials. In this thesis the charge carrier photogeneration mechanisms in conductive polymers are systematized starting from the extensive and detailed literature review. The photocarrier transport and recombination are also considered. The polymer photodetector model is developed consisting of the continuity and diffusion equation for singlet excitons and the continuity and drift-diffusion equation for hole polarons. The model is applied to the ITO/PEDOT:PSS/MEH-PPV/A1 detectors. The photocurrent spectra for the devices with three different thin film thicknesses (35 nm, 100 nm i 215 nm) in the wide range of incident light intensities (10-4 mW/cm2 - 10-2 mW/cm2) and bias voltages (-8 V to +1 V) are measured and compared with the model predictions. Based on the comprehensive photocurrent spectra analysis the thickness dependence of the MEH-PPV absorption coefficient is discovered. The revealed dependence is experimentally confirmed. It is also shown that polaron photogeneration quantum efficiency for this polymer changes with the film thickness. The ITO/PEDOT:PSS/MEH-PPV/Al photocurrent spectra are reproduced very well by the model for all devices and operating conditions used in the experiment.

Zahvaljujući brojnim prednostima u odnosu na klasične poluprovodnike provodni polimeri spadaju u grupu najperspektivnijih optoelektronskih materijala. Da bi sav njihov potencijal bio iskorišćen neophodno je rasvetliti složene fizičke procese koji se u ovim materijalima odvijaju. U okviru ove doktorske disertacije izvršena je sistematizacija mehanizama fotogeneracije nosilaca naelektrisanja u provodnim polimerima polazeći od opsežnog i detaljnog pregleda literature. Transport i rekombinacija fotonosilaca su, takođe, razmatrani. Razvijen je eksitonsko-polaronski model polimerskog fotodetektora zasnovan na jednačini kontinuiteta i difuzionoj jednačini za singletne eksitone i jednačini kontinuiteta i drift-difuzionoj jednačini za šupljinske polarone. Model je primenjen na ITO/REDOT:R55/MENRRV/A1 naprave. Simulirani spektri fotostruje upoređeni su sa izmerenim za detektore sa tri različite debljine MEN-RRV filma (35 nm, 100 nm i 215 nm) u širokom opsegu intenziteta upadne svetlosti (10-4 mW/cm2 - 10-2 mW/cm2) i napona polarizacije (-8 V do +1 V). Na osnovu sveobuhvatne analize spektra fotostruje otkrivena je zavisnost koeficijenta apsorpcije MEN-RRV-a od debljine tankog filma. Dobijena zavisnost je i eksperimentalno potvrđena. Takođe, pokazano je da se i kvantna efikasnost fotogeneracije polarona menja sa promenom debljine polimerskog filma. Model dobro reprodukuje spektar fotostruje za sve naprave i uslove rada obuhvaćene eksperimentom.

Subjects/Keywords: conductive polymers; photophysics; modeling; photodetector; provodni polimeri; fotofizika; modelovanje; fotodetektor

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APA (6^th Edition):

Jovana, P. (2012). The analysis of the charge carrier photogeneration and recombination in conductive polymers: Photodetector applications. (Doctoral Dissertation). University of Belgrade. Retrieved from http://dx.doi.org/10.2298/BG20120620PETROVIC ; http://eteze.bg.ac.rs/application/showtheses?thesesId=226 ; https://fedorabg.bg.ac.rs/fedora/get/o:5486/bdef:Content/get ; http://vbs.rs/scripts/cobiss?command=SEARCH&base=99999&select=ID=43463439

Chicago Manual of Style (16^th Edition):

Jovana, Petrović. “The analysis of the charge carrier photogeneration and recombination in conductive polymers: Photodetector applications.” 2012. Doctoral Dissertation, University of Belgrade. Accessed September 16, 2019. http://dx.doi.org/10.2298/BG20120620PETROVIC ; http://eteze.bg.ac.rs/application/showtheses?thesesId=226 ; https://fedorabg.bg.ac.rs/fedora/get/o:5486/bdef:Content/get ; http://vbs.rs/scripts/cobiss?command=SEARCH&base=99999&select=ID=43463439.

MLA Handbook (7^th Edition):

Jovana, Petrović. “The analysis of the charge carrier photogeneration and recombination in conductive polymers: Photodetector applications.” 2012. Web. 16 Sep 2019.

Vancouver:

Jovana P. The analysis of the charge carrier photogeneration and recombination in conductive polymers: Photodetector applications. [Internet] [Doctoral dissertation]. University of Belgrade; 2012. [cited 2019 Sep 16]. Available from: http://dx.doi.org/10.2298/BG20120620PETROVIC ; http://eteze.bg.ac.rs/application/showtheses?thesesId=226 ; https://fedorabg.bg.ac.rs/fedora/get/o:5486/bdef:Content/get ; http://vbs.rs/scripts/cobiss?command=SEARCH&base=99999&select=ID=43463439.

Council of Science Editors:

Jovana P. The analysis of the charge carrier photogeneration and recombination in conductive polymers: Photodetector applications. [Doctoral Dissertation]. University of Belgrade; 2012. Available from: http://dx.doi.org/10.2298/BG20120620PETROVIC ; http://eteze.bg.ac.rs/application/showtheses?thesesId=226 ; https://fedorabg.bg.ac.rs/fedora/get/o:5486/bdef:Content/get ; http://vbs.rs/scripts/cobiss?command=SEARCH&base=99999&select=ID=43463439

Vrije Universiteit Amsterdam

27. Ravensbergen, J. Photophysics of solar fuel materials .

Degree: 2015, Vrije Universiteit Amsterdam

URL: http://hdl.handle.net/1871/53504

Subjects/Keywords: photophysics; solar fuel; spectroscopy

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APA (6^th Edition):

Ravensbergen, J. (2015). Photophysics of solar fuel materials . (Doctoral Dissertation). Vrije Universiteit Amsterdam. Retrieved from http://hdl.handle.net/1871/53504

Chicago Manual of Style (16^th Edition):

Ravensbergen, J. “Photophysics of solar fuel materials .” 2015. Doctoral Dissertation, Vrije Universiteit Amsterdam. Accessed September 16, 2019. http://hdl.handle.net/1871/53504.

MLA Handbook (7^th Edition):

Ravensbergen, J. “Photophysics of solar fuel materials .” 2015. Web. 16 Sep 2019.

Vancouver:

Ravensbergen J. Photophysics of solar fuel materials . [Internet] [Doctoral dissertation]. Vrije Universiteit Amsterdam; 2015. [cited 2019 Sep 16]. Available from: http://hdl.handle.net/1871/53504.

Council of Science Editors:

Ravensbergen J. Photophysics of solar fuel materials . [Doctoral Dissertation]. Vrije Universiteit Amsterdam; 2015. Available from: http://hdl.handle.net/1871/53504

Bowling Green State University

28. Neupane, Chandra Prasad, Neupane. Time Resolved Optical Spectroscopy of Colloidal PbS Nanosheets.

Degree: MS, Physics, 2018, Bowling Green State University

URL: http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1530805332385177

► Highly luminescent few-atoms thick colloidal PbS nanosheets are a promising material for the applications in infrared optoelectronics and photonics since a large in-plane charge carrier… (more)

Subjects/Keywords: Physics; Nanoscience; Photophysics; PbS nanosheets; PbSe nanorods; Carbon dots

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APA (6^th Edition):

Neupane, Chandra Prasad, N. (2018). Time Resolved Optical Spectroscopy of Colloidal PbS Nanosheets. (Masters Thesis). Bowling Green State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1530805332385177

Chicago Manual of Style (16^th Edition):

Neupane, Chandra Prasad, Neupane. “Time Resolved Optical Spectroscopy of Colloidal PbS Nanosheets.” 2018. Masters Thesis, Bowling Green State University. Accessed September 16, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1530805332385177.

MLA Handbook (7^th Edition):

Neupane, Chandra Prasad, Neupane. “Time Resolved Optical Spectroscopy of Colloidal PbS Nanosheets.” 2018. Web. 16 Sep 2019.

Vancouver:

Neupane, Chandra Prasad N. Time Resolved Optical Spectroscopy of Colloidal PbS Nanosheets. [Internet] [Masters thesis]. Bowling Green State University; 2018. [cited 2019 Sep 16]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1530805332385177.

Council of Science Editors:

Neupane, Chandra Prasad N. Time Resolved Optical Spectroscopy of Colloidal PbS Nanosheets. [Masters Thesis]. Bowling Green State University; 2018. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1530805332385177

Vanderbilt University

29. Reid, Kemar Ricardo. Unraveling the Interplay between Structure and Photophysics in Colloidal Quantum Dot Nanostructures.

Degree: PhD, Interdisciplinary Materials Science, 2019, Vanderbilt University

URL: http://etd.library.vanderbilt.edu/available/etd-03072019-232233/ ;

► Colloidal quantum dots (QDs) make up a class of nanomaterials that provide a remarkable platform for engineering photophysical properties tailored to a range of applications… (more)

▼ Colloidal quantum dots (QDs) make up a class of nanomaterials that provide a remarkable platform for engineering photophysical properties tailored to a range of applications of considerable technological value, including energy-efficient LEDs, robust biological probes, low-threshold solution-processed lasers, advanced photocatalysts and single-photon sources for quantum technologies. Underpinning these uses of QDs lay more fundamental investigations into the role of structure on absorption, energy relaxation, charge separation and charge recombination in order to achieve complete control over their photophysical behavior. However, with complex interfaces and diverging morphologies in synthetic products, QDs are remarkably complex nanostructured materials. It is therefore challenging to develop detailed structure-function relationships at the ensemble scaleâwhere the properties of an array of structures are simultaneously determined. To decode this information, it is necessary to study QD nanostructures one at a time. In this work, single QD investigations were applied to three different QD systems to better understand the interplay between structure and photophysics in these materials. From revealing the role of strain-induced structural changes on the color purity of CdSe-CdS core-shell QDs, to a thick-shell in suppressing random intermittent emission in cadmium-free InP QD nanostructures, these investigations continually point to the negative impact of structural heterogeneity on the properties of the ensemble. The implementation of a correlative technique to measure the structure and photophysics of the same QD facilitated a detailed examination of this heterogeneity in semiconductor nanorodsârevealing the detrimental effects of surface roughness on the quantum efficiency of the material. The advanced characterization of QDs afforded by this technique also has far-reaching implications for QD development and could be used to inform methods to orchestrate the assembly of QD nanostructures with precisely tuned photophysical properties. Advisors/Committee Members: Jason G. Valentine (committee member), Janet E. Macdonald (committee member), Richard F. Haglund (committee member), Rizia Bardhan (committee member), Sandra J. Rosenthal (chair).

Subjects/Keywords: photophysics; atomic structure; electron microscopy; optical spectroscopy; correlation; quantum dot

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APA (6^th Edition):

Reid, K. R. (2019). Unraveling the Interplay between Structure and Photophysics in Colloidal Quantum Dot Nanostructures. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://etd.library.vanderbilt.edu/available/etd-03072019-232233/ ;

Chicago Manual of Style (16^th Edition):

Reid, Kemar Ricardo. “Unraveling the Interplay between Structure and Photophysics in Colloidal Quantum Dot Nanostructures.” 2019. Doctoral Dissertation, Vanderbilt University. Accessed September 16, 2019. http://etd.library.vanderbilt.edu/available/etd-03072019-232233/ ;.

MLA Handbook (7^th Edition):

Reid, Kemar Ricardo. “Unraveling the Interplay between Structure and Photophysics in Colloidal Quantum Dot Nanostructures.” 2019. Web. 16 Sep 2019.

Vancouver:

Reid KR. Unraveling the Interplay between Structure and Photophysics in Colloidal Quantum Dot Nanostructures. [Internet] [Doctoral dissertation]. Vanderbilt University; 2019. [cited 2019 Sep 16]. Available from: http://etd.library.vanderbilt.edu/available/etd-03072019-232233/ ;.

Council of Science Editors:

Reid KR. Unraveling the Interplay between Structure and Photophysics in Colloidal Quantum Dot Nanostructures. [Doctoral Dissertation]. Vanderbilt University; 2019. Available from: http://etd.library.vanderbilt.edu/available/etd-03072019-232233/ ;

University of Rochester

30. Larkin, John Michael (1970 - ). Optical and photodynamic properties of higher-lying states of rose bengal.

Degree: PhD, 2007, University of Rochester

URL: http://hdl.handle.net/1802/4370

► We have studied the photophysics and photochemistry of the higher-lying triplet states of rose bengal (tetraiodo-tetrachlorofluorescein) in water. Triplet-triplet absorption spectroscopy is used to identify… (more)

▼ We have studied the photophysics and photochemistry of the higher-lying triplet states of rose bengal (tetraiodo-tetrachlorofluorescein) in water. Triplet-triplet absorption spectroscopy is used to identify a previously undescribed triplet state of rose bengal with an absorption cross section of (1.1 ± 0.1) × 10⁻¹⁶ cm² at 1064 nm. This state is the least energetic triplet state, excluding T₁, to be identified, so it will be denoted as T₂. Two-step excitation techniques for measuring reverse intersystem crossing, an intersystem crossing from a higher-lying triplet state to a singlet state, are described. The method of two-step laser-induced fluorescence is used to determine the quantum yield of reverse intersystem crossing for three higher-lying triplet states of rose bengal. Reverse intersystem crossing yields of 0.0076 ± 0.0002, <0.06, and 0.12 ± 0.02 are found for the triplet states excited by 1064-, 632-, 532-nm light, denoted respectively as T₂, T₃ and T₄. Bond cleavage may also follow excitation of a higher-lying state. Other workers have found evidence for this photochemical process from T₃ but not T₄. The method of two-step laser-induced bleaching was used to determine whether bond cleavage occurs from T₂. No evidence was found for a such a process. It had been hypothesized that reverse intersystem crossing was responsible for the lack of bond cleavage from T₄. A theoretical investigation based on kinetic models including reverse intersystem crossing shows that variations in the yield of this process would produce only small changes in the yield of photoproducts formed by bond cleavage. A two-photon absorption cross section of 0.028 ± 0.001 GM for rose bengal excited by 1064-nm light is determined using a fluorescence technique. The impact of higher-lying states on multiphoton excitation is discussed, and it is shown that the neglect of reverse intersystem crossing can lead to an apparent enhancement of the two-photon absorption cross section in the analysis of fluorescence data.

Subjects/Keywords: Tetraiodo-tetrachlorofluorescein; Photophysics; Photochemistry

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APA (6^th Edition):

Larkin, J. M. (. -. ). (2007). Optical and photodynamic properties of higher-lying states of rose bengal. (Doctoral Dissertation). University of Rochester. Retrieved from http://hdl.handle.net/1802/4370

Chicago Manual of Style (16^th Edition):

Larkin, John Michael (1970 - ). “Optical and photodynamic properties of higher-lying states of rose bengal.” 2007. Doctoral Dissertation, University of Rochester. Accessed September 16, 2019. http://hdl.handle.net/1802/4370.

MLA Handbook (7^th Edition):

Larkin, John Michael (1970 - ). “Optical and photodynamic properties of higher-lying states of rose bengal.” 2007. Web. 16 Sep 2019.

Vancouver:

Larkin JM(-). Optical and photodynamic properties of higher-lying states of rose bengal. [Internet] [Doctoral dissertation]. University of Rochester; 2007. [cited 2019 Sep 16]. Available from: http://hdl.handle.net/1802/4370.

Council of Science Editors:

Larkin JM(-). Optical and photodynamic properties of higher-lying states of rose bengal. [Doctoral Dissertation]. University of Rochester; 2007. Available from: http://hdl.handle.net/1802/4370

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