Dissertations / Theses: 'Photophysical Chemistry'

1

Conn, Pauline Frances. "Photophysical chemistry of carotenoids." Thesis, Keele University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315187.

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Dosche, Carsten, Hans-Gerd Löhmannsröben, A. Bieser, P. I. Dosa, S. Han, M. Iwamoto, A. Schleifenbaum, and K. Peter C. Vollhardt. "Photophysical properties of [N]phenylenes." Universität Potsdam, 2002. http://opus.kobv.de/ubp/volltexte/2007/1193/.

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In the present study, photophysical properties of [N]phenylenes were studied by means of stationary and time-resolved absorption and fluorescence spectroscopy (in THF at room temperature). For biphenylene (1) and linear [3]phenylene (2a), internal conversion (IC) with quantum yields ΦIC > 0.99 is by far the dominant mechanism of S1 state deactivation. Angular [3]phenylene (3a), the zig-zag [4]- and [5]phenylenes (3b), (3c), and the triangular [4]phenylene (4) show fluorescence emission with fluorescence quantum yieds and lifetimes between ΦF = 0.07 for (3a) and 0.21 for (3c) and τF = 20 ns for (3a) and 81 ns for (4). Also, compounds (3) and (4) exhibit triplet formation upon photoexcitation with quantum yields as high as ΦISC = 0.45 for (3c). The strong differences in the fluorescence properties and in the triplet fromation efficiencies between (1) and (2a) on one hand and (3) and (4) on the other are related to the remarkable variation of the internal conversion (IC) rate constants kIC. A tentative classification of (1) and (2a) as “fast IC compounds”, with kIC > 109 s-1, and of (3) and (4) as “slow IC compounds”, with kIC ≈ 107 s-1, is suggested. This classification cannot simply be related to Hückel’s rule-type concepts of aromaticity, because the group of “fast IC compounds” consists of “antiaromatic” (1) and “aromatic” (2a), and the group of “slow IC compounds” consists of “antiaromatic” (3b), (4) and “aromatic” (3a), (3c). The IC in the [N]phenylenes is discussed within the framework of the so-called energy gap law established for non-radiative processes in benzenoid hydrocarbons.

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Lin, Liangbih. "Photophysical studies of ring containing conjugated polymers." The Ohio State University, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=osu1343061430.

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Mickenberg, Seth F. (Seth Fox). "Tuning the photophysical properties of amidophosphine complexes of copper." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/49753.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2009.
Vita.
Includes bibliographical references (leaves 23-24).
A series of monomeric copper complexes that allow for the tuning of the emission properties is reported. Luminescence lifetimes up to 150 [mu]s are observed in benzene solution at ambient temperature, which are comparable to the lifetimes of the longest-lived previously reported copper luminophores. These complexes also exhibit quantum yields up to 0 = 0.70 at 298 K. The results of time-dependent density functional theory (TDDFT) calculations indicate emission from a triplet state in all cases. The calculations also successfully correlate the energy of the transition from this triplet state to the energy of the observed emission. Such luminescence from a first-row metal is highly unusual, especially when considering the phosphine-based ligand framework used.
by Seth F. Mickenberg.
S.M.

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Bradley, Patricia Marie. "Photochemistry and photophysical properties of metal-metal dimer complexes /." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486461246814571.

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Liska, Tadeas. "Bis(imidazolyl)carbazolide Platinum(II) Alkynyls: Synthesis, Characterization, and Photophysical Properties." Case Western Reserve University School of Graduate Studies / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=case1626960987919156.

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Rogge, Carsten. "Photophysical studies of organic dyes in polymer matrices." Thesis, Cranfield University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266485.

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Kelly, Graeme P. "Photochemical and photophysical properties of various triaryl-2-pyrazolines." Thesis, Loughborough University, 1987. https://dspace.lboro.ac.uk/2134/28194.

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The main aim of the research was to obtain a detailed insight into the photochemical and photophysical properties of various triaryl-2- pyrazolines, with a view to understanding better their role in photoconductive materials. The technique of laser flash photolysis, in both transmission and diffuse reflectance mode, was employed to study the compounds as microcrystalline powders, within polymer films, on fabrics and in solution. In those media where the triplet state was not directly observed it was sensitized with a suitable triplet energy donor such as benzophenone.

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Wallace, Sheena J. L. "Photophysical studies of hydrophobically-modified poly(N,N-dimethylacrylamide)." Thesis, Lancaster University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242818.

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Chretien, Michelle N. "Photochemical, photophysical, and photobiological studies of zeolite guest-host complexes." Thesis, University of Ottawa (Canada), 2005. http://hdl.handle.net/10393/29205.

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This thesis focuses on the photochemistry and photophysics of a variety of zeolite complexes, from catalysts to sunscreens. The first chapter describes the preparation and photophysical and photochemical characterization of two new photocatalytic materials. The catalysts are based on a multi-component zeolite, host-guest complex and the interaction between components was probed using time-resolved spectroscopic techniques. The catalytic efficiency, in terms of the ability to photodegrade biological contaminants, was also investigated. These studies were performed with the aim of developing efficient catalysts for wastewater remediation which can be used with solar (visible) radiation. In subsequent chapters, zeolite materials have been used as matrices for the stabilization of various transient or reactive species. In the case of ZSM-5-type zeolite, the dibenzotropylium cation was rendered indefinitely persistent allowing the examination of its excited-state behaviour. The geometric restriction within the cavities also permits the observation of electron transfer chemistry in the absence of a nucleophilic addition reaction with the electron donor. In a second example, ketoprofen (a non-steroidal anti-inflammatory drug) was found to undergo intrazeolite photodecarboxylation to generate a benzylic carbanion. The lifetime of the zeolite-encapsulated carbanion was found to be fifty times longer than in solution. The enhanced lifetime allows intermolecular nucleophilic addition chemistry to compete with protonation, effectively, a photo-initiated Grignard-type reaction is observed. In Chapter 6, fluorescence is used as tool to probe both intra- and interzeolite interactions. In the first part, a zeolite-entrapped radical probe was prepared by ship-in-a-bottle synthesis for the investigation of radical percolation in the zeolite matrix. The probe is a molecular dyad containing a persistent free-radical and a quenched fluorophore. When the probe radical couples with a carbon-centered radical, the probe fluorescence is restored and in this way free-radical species in heterogeneous systems can be conveniently examined. In the second section, zeolite particles were irreversibly labeled with a biologically-compatible fluorophore (also by ship-in-a-bottle synthesis). The last part of this thesis deals with a project relating to supramolecular sunscreens. (Abstract shortened by UMI.)

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Jones, Derek R. "Design, Synthesis, and Photophysical Properties of Corannulene-based Organic Molecules." University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1323350004.

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Wilkinson, Terence Sean. "Photophysical studies of waterborne polymer colloids and their film formation." Thesis, Lancaster University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302429.

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Leed, Nicholas Alexander. "Photophysical Properties and Control of the Excited State of Transition Metal Complexes." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1368115489.

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Alsindi, Wassim Zuhair. "Solvent based switching of photophysical properties of transition metal complexes." Thesis, University of Nottingham, 2007. http://eprints.nottingham.ac.uk/13786/.

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The work presented in this Thesis describes the modular design and spectroscopic study of polynuclear systems based on ruthenium (II) and rhenium (I) complexes. A combination of UV/vis, luminescence and TRIR spectroscopies, electrochemistry, spectroelectrochemistry and conformational analysis have been employed to understand the electronic structure of the ground and excited states of these compounds. Chapter I gives an introductory background to this Thesis. An overview of transition metal photophysics and excited states, and the typical spectroscopic and electrochemical techniques used in their study is presented. Previous studies of the ground and excited state properties of the complexes [Ru(bpy)3]2+ and [ReCl(CO)3bpy)] which are used as supramolecular building blocks in this Thesis are presented and a number of relevant studies of supramolecular systems are described. Chapter 2 contains a study extending the known family of [Ru(CN)4(NN)]2- complexes and describes their unique advantages over [Ru(bpy)3]2+. The results obtained are discussed alongside previous studies. This completes the introduction of the molecular building blocks used in Chapters 3 and 4. Chapter 3 details a study of through-space PEnT in bimetallic systems constructed from the complexes introduced in Chapters I and 2, bridged by a saturated alkyl linker between bpy ligands on either metal. This Chapter demonstrates the solvent-switchable nature of the direction and gradient of PEnT, using ps-TRIR spectroscopy to directly probe these processes in real time. Chapter 4 describes a study of bimetallic systems bridged by conjugated the ligand 2,2'- bipyrimidine. Monometallic, homobimetallic and heterobimetallic systems are studied and questions arising from limitations of previous studies are addressed. In particular ps-TRIR spectroscopy gives new insight into the numerous ultrafast processes occurring. Chapter 5 summarises the achievements of this Thesis and suggests promising directions for extending this work in the future. Chapter 6 describes the experimental and theoretical techniques used in this Thesis.

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Stanley, Claire Frances. "Photophysical evaluation of substituted zinc phthalocyanines as sensitisers for photodynamic therapy." Thesis, Durham University, 1997. http://etheses.dur.ac.uk/4681/.

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Zinc phthalocyanines (ZnPc) are currently being investigated in relation to their use as sensitisers for Photodynamic Therapy (PDT). In particular, the photophysical properties of these dyes are of interest since then- ability to generate the cytotoxic species, singlet oxygen ((^1)O(_2)), is believed to be central to their role in causing tumour necrosis. In this study, a detailed investigation of the photophysical properties of substituted zinc phthalocyanines under various conditions is described. Two novel β-tetra substituted zinc phthalocyanines have been synthesised, ZnPc(CMe(C0(_2)Me)(_2))(_4) and ZnPc(CHMeCO(_2)H)(_4). The nature of peripheral substituents has little effect on triplet state or singlet oxygen production by ZnPc, however, ZnPc(CHMeCO(_2)H)(_4) displays a remarkable sensitivity to the ionic strength of non aqueous solutions. Ion concentrations below 10(^-4) mol dm(^-3) induce dimerisation whilst concentrations greater than this promote monomerisation. This behaviour is attributed to ion pairing effects. Photophysical properties of substituted zinc phthalocyanines in heterogenous media and on solid substrates are also described. The temperature and pH of solvent media greatly influence the photophysical properties of phtiialocyanines. Octadecyl zinc phthalocyanine (C10) aggregates upon cooling to 77 K in ether-pentane-alcohol (5:5:2) solution. Additional structure in the absorption spectrum is observed, accompanied by the appearance of a fluorescence emission band at 760 nm. Aluminium phthalocyanine chloride in methanol dimerises upon addition of 2.5 x 10(^-5) mol dm(^-3) fluoride ions. Dimer species are characterised by a blue shifted peak in the absorption spectrum and are non-fluorescent. These results are ascribed to different aggregate geometries and discussed in terms of exciton theory. Low pH induces stepwise protonation of the azomethine bridges of the phthalocyanme ring, Pc + nH(^+) PcH(_n)(^n+)+, where n = 0 to 4. Protonation results in significant changes in absorption, fluorescence and triplet state properties of the phthalocyanine. A dramatic decrease in singlet oxygen generation by the phthalocyanine (ɸ∆ (n = 0) = 0.54, ɸ∆ (n = 1) = 0.075) is reported, and occurs under surprisingly mild conditions (pK(_a) of ZnPcS(_2) in 1% Triton X-100/H(_2)O = 4.4). The propensity of ZnPc's to bind to serum protein and to participate in electron transfer reactions with potential electron donors is discussed.

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Young, Philip Jordan. "The Effect of Boron on the Photophysical Properties of Dimetal Quadruply Bonded Complexes." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1436355107.

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Azizi, Fereshteh. "Photophysical properties of single and double stranded DNA containing 6-phenylpyrrolocytosine (PHPC)." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=117130.

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Fluorescence spectroscopy has proven a valuable technique for studying the structure and function of nucleic acids and other essential molecules in cellular biology. In this regard, intrinsic fluorescent nucleobase analogues are widely used to probe structural and dynamic properties of nucleic acids. Due to its unique emissive properties, 6-Phenylpyrrolo-2'-deoxycytosine (dPhpC), a novel fluorescent deoxycytosine analog, is a suitable fluorescent reporter that has been exploited to study the structure, dynamics and localization of nucleic acids. dPhpC possesses several desirable properties, including high quantum yield and sensitivity to changes in the surrounding microenvironment. Given the increasing demand for unobtrusive fluorescent probes for use in biochemical studies, dPhpC is an attractive fluorophore that mimics cytosine with respect to nucleic acid base pairing and enzyme interactions. To use this molecular probe to its full potential, it is essential to elucidate the interactions between dPhpC and its inter- and intra-strand neighbouring nucleotides, and the effect of these interactions on the fluorescent properties of dPhpC. With this information in hand, dPhpC can be employed as a highly sensitive molecular probe for studying a wide variety of nucleic acid-based systems, and fluorescent PhpC-containing oligonucleotides can be readily optimized for specific purposes.In this thesis, we synthesized 6-phenylpyrrolo-2'-deoxycytidine (dPhpC) and incorporated it into single and double stranded DNA. This work demonstrates that the nature and orientation of nucleoside neighbours surrounding dPhpC significantly affect its fluorescent properties. According to the results presented in this work, the average fluorescence quantum yields for dPhpC-containing single strands is greater than those of their corresponding double-strands. Several rules for predicting and optimizing the properties of dPhpC-containing oligonucleotides are also identified: neighboring adenine causes a significant increase in dPhpC fluorescent intensity, guanine most effectively quenches fluorescence, and the orientation of neighbors around dPhpC significantly affects dPhpC quantum yield (e.g. the quenching effect of guanine is higher when it is placed at the 3'-side of dPhpC). Overall, our studies allow us to better predict dPhpC fluorescence changes upon incorporation in DNA structures, greatly facilitating the design of optimized dPhpC-containing nucleic acid probes for use in a wide variety of fluorescence studies.
La spectroscopie de fluorescence s'est avérée une technique précieuse pour étudier la structure et la fonction des acides nucléiques et d'autres molécules essentielles en biologie cellulaire. À cet égard, les analogues de nucléoside fluorescentes intrinsèques sont largement utilisés pour sonder les propriétés structurales et dynamiques des acides nucléiques. À cause de ses propriétés émissives uniques, 6-phénylpyrrolo-2'-déoxycytosine (dPhpC), un nouvel analogue fluorescent de la déoxycytosine, est un reporter fluorescent approprié qui a été exploitée pour étudier la structure, la dynamique et la localisation des acides nucléiques. dPhpC possède plusieurs propriétés souhaitables, notamment le rendement quantique élevé et une sensibilité à des changements dans le micro-environnement environnant. Compte tenu de la demande croissante de discrètes sondes fluorescentes pour utilisation dans des études biochimiques, dPhpC est un fluorophore attrayant qui imite la cytosine par rapport au couplage d'acide nucléique de base et les interactions enzymatiques. Pour utiliser cette sonde moléculaire à son plein potentiel, il est essentiel d'élucider les interactions entre dPhpC et ses nucléotides voisins inter- et intra-brin, et l'effet de ces interactions sur les propriétés fluorescentes de dPhpC. Avec cette information, dPhpC peut être utilisé comme une sonde moléculaire très sensible pour l'étude d'une grande variété des systèmes à base de acides nucléiques, et les oligonucléotides fluorescentes contenant du PhpC peuvent être facilement optimisé à des fins spécifiques. Dans cette thèse, nous avons synthétisé 6-phénylpyrrolo-2'-désoxycytidine (dPhpC) et l'ont incorporé dans l'ADN simple et double brin. Ce travail démontre que la nature et l'orientation des voisins nucléosidiques entourant dPhpC affecter de manière significative ses propriétés fluorescentes. Selon les résultats présentés dans ce travail, les rendements quantiques de fluorescence moyenne pour dPhpC contenant des simples brins est supérieure à celles de leurs doubles brins correspondants. Plusieurs règles pour la prédiction et l'optimisation des propriétés des oligonucléotides contenant dPhpC sont également identifiées: l'adénine voisin entraîne une augmentation significative de l'intensité de fluorescence de dPhpC, la guanine plus efficacement étanche fluorescence, et l'orientation des voisins autour dPhpC affecte de manière significative le rendement quantique de dPhpC (par exemple l'effet d'extinction de la guanine est plus élevée lorsqu'il est placé à l'extrémité 3 'du côté dPhpC). Dans l'ensemble, nos études permettez-nous de prévoir mieux les changements de fluorescence de dPhpC sur l'incorporation en structures d'ADN, ce qui facilite grandement la conception d'optimisation dPhpC contenant des sondes d'acides nucléiques pour utilisation dans une grande variété d'études de fluorescence.

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Lai, Siu-wai, and 黎小慧. "Luminescent organoplatinum chemistry: photophysical and supramolecular properties of metallacyclic andpolypyridine platinum(II) complexes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31238737.

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Alemán, Elvin A. "PHOTOCHEMISTRY AND PHOTOPHYSICAL CHARACTERIZATION OF PORPHYRIN & N-CONFUSED PORPHYRIN DYADS: PORPHYRIN PHOTOPHYSICAL PROPERTIES AND ELECTRON AND ENERGY TRANSFER." University of Akron / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=akron1161633478.

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Jacoby, Kimberly Joy. "ENZYMATIC SYNTHESIS AND PHOTOPHYSICAL CHARACTERIZATION OF DUALLY FLUORESCENT FLAVIN ADENINE DINUCLEOTIDE COFACTORS." Diss., Temple University Libraries, 2016. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/398191.

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Chemistry
Ph.D.
ABSTRACT Many enzymes require cofactors in order to carry out specific functions. Flavins, which are naturally fluorescent, compose a unique group of redox cofactors because they have the ability to transfer one or two electrons and are therefore found in three different oxidation states. A specific flavin, flavin adenine dinucleotide (FAD), is a crucial cofactor that facilitates electron transfer in many flavoproteins involved in DNA repair, photosynthesis, and regulatory pathways. One example of a FAD-containing DNA repair protein is DNA Photolyase (PL). E. coli PL is a monomeric flavoprotein that facilitates DNA repair via a photoinduced electron transfer reaction. The catalytic cofactor, FAD, transfers an electron to a thymidine dimer lesion, to cleave the cyclobutane ring and restore the DNA strand. Although the mechanism of repair has been partially elucidated by our group, it is still unclear whether or not the electron is transferred directly from the isoalloxazine moiety to the dimer or if the electron hops from the isoalloxazine moiety to the adenine moiety to the dimer. This sequential hopping mechanism should have excited state absorption features for the reduced flavin species, an adenine radical anion, and the semiquinone flavin species. To investigate the mechanistic role of adenine, E. coli PL has been reconstituted with -FAD, an FAD analogue in which the adenine was substituted via chemical means with 1,N6 – ethenoadenine dinucleotide. -FAD was selected due to its ease of synthesis and because its structure changes the thermodynamic driving force for the electron transfer reaction, by lowering the energetic gap (LUMO-LUMO) between the isoalloxazine ring and the modified adenine. In order to characterize the excited state dynamics of the mutant chromophore, the transient absorption measurements were made of each free flavin in solution. These measurements indicate the pathway of electron transfer must be mediated via superexchange rather than a hopping mechanism. This important result shows that the role of adenine in photolyase is to facilitate a superexchange electron transfer mechanism, and a modified flavin can act as a reporter under these experimental conditions. By exploiting Corynebacterium ammoniagenes FAD synthetase adenylation promiscuity, we have enzymatically-synthesized and purified a novel dually fluorescent flavin cofactor. This new flavin adenine dinucleotide (FAD) analogue, flavin 2-aminopurine (2Ap) dinucleotide (F2ApD), can be selectively excited through the 2Ap moiety at 310 nm, a wavelength at which flavins have intrinsically low extinction. The dinucleotide 2Ap emits at 370 nm with high efficiency. This emission has excellent overlap with the absorption spectra of both oxidized and reduced hydroquinone flavin (FlOX and FlHQ respectively), which emit at ~525 and ~505 nm respectively. We have characterized the optical properties of this dually fluorescent flavin, iFAD. Steady state fluorescence excitation and emission spectra were obtained and contrasted with the other flavins. Temperature- and solvent-dependent emission spectra suggest that F2ApD stacking interactions are significantly different compared to FAD and etheno-FAD (FAD). The optical absorption spectra of these dinucleotides were compared with FMN to explore electronic interactions between the flavin and nucleobase moieties. To probe the evolution of the different excited state populations, femtosecond transient absorption measurements were made on the iFADs, revealing that F2ApD exhibited unique transient spectra as compared to either FAD or FAD. The significance of these results to flavins, flavoprotein function, and bioimaging are discussed. The reconstituted -FAD in E.coli photolyase was catalytically active and actually repaired more efficiently than the FAD-reconstituted photolyase. To validate that an enzymatically synthesized iFAD could be reconstituted into a flavoprotein, this work shows a DNA repair assay using F2ApD that was reconstituted into E. coli photolyase, generating the reconstituted analogue, ApPL. Activity assays were compared between FAD-PL and ApPL. This comparison further elucidates the importance of the driving force on the electron transfer reaction in PL. A comparison of fluorescence spectroscopies between the reconstituted PLs highlights their applicability as biosensors and/or mechanistic reporters.
Temple University--Theses

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Savage, Alison Clare. "Controlled coating of nanoparticles with peptides and lanthanide complexes : a photophysical evaluation." Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/4958/.

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This thesis describes the co-coating of gold nanoparticles with different combinations of lanthanide complexes and peptides, and the effect of this co-coating on the photophysical properties of the lanthanide complexes has been examined. A photophysical study of europium (III) ions binding to two surface active peptides in solution is presented and the ability of these peptides to bind the europium ions whilst tethered to gold nanoparticles is discussed. Lanthanide complexes with a diethylenetriaminepentaacetic acid (DTPA) binding motif were prepared and attached to gold nanoparticles with different peptides to investigate their photophysical properties and their potential as a cellular imaging agent has been demonstrated. The co-coating of gold nanoparticles with europium and gadolinium complexes is also introduced, and these nanoparticles have the potential to be used as a multi-modal imaging agent for luminescent and magnetic resonance imaging. The synthesis of an azo-dye has been undertaken and its ability to bind and sensitise the near infrared lanthanides neodymium (III) and ytterbium (III) has been demonstrated. It was found to form complexes with these lanthanides, and the high molar absorption coefficients in the visible region allows for excitation at wavelengths up to 500 nm.

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Demshemino, Innocent Sunday. "Synthesis and Photophysical Studies of Self-Assembled Chromophores." University of Akron / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=akron1590713830617676.

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Viswanathan, Subha. "Nitro- and oxazoline-derivatized antennas structural and photophysical characterization of their lanthanide complexes /." Related electronic resource:, 2007. http://proquest.umi.com/pqdweb?did=1362530571&sid=2&Fmt=2&clientId=3739&RQT=309&VName=PQD.

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Altamimi, Rashid M. "Synthesis and Photophysical Properties of Porphyrin-Containing Supramolecular Systems." University of Akron / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=akron1291171941.

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Lai, Siu-wai. "Luminescent organoplatinum chemistry : photophysical and supramolecular properties of metallacyclic and polypyridine platinum(II) complexes /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20792943.

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Redmond, R. W. "On the photophysical properties of Haematoporphyrin and related species used in cancer phototherapy." Thesis, University of the West of Scotland, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355856.

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Garrison, Shana A. "SYNTHESIS AND PHOTOPHYSICAL CHARACTERIZATION OF PORPHYRIN-CONTAINING SUPRAMOLECULAR SYSTEMS: STRUCTURAL ISSUES FOR PORPHYRIN PHOTOPHYSICS AND ELECTRON TRANSFER." Akron, OH : University of Akron, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=akron1123616344.

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Thesis (Ph. D.)--University of Akron, Dept. of Chemistry, 2005.
"August, 2005." Title from electronic dissertation title page (viewed 09/24/2005). Advisor, David A. Modarelli; Committee members, Matthew Espe, Michael Taschner, Chrys Wesdemiotis, Stephanie Lopina; Department Chair, David Perry; Dean of the College, Charles B. Monroe; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.

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Phillips, Sarah F. "A photophysical characterization on the unique properties of perylene-3,4:9,10-BIS((3,4,5(tris(octyloxy)benzohydrazide)-dicarboximide." Akron, OH : University of Akron, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=akron1249081748.

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Thesis (M.S.)--University of Akron, Dept. of Chemistry, 2009.
"August, 2009." Title from electronic thesis title page (viewed 10/14/2009) Advisor, David A. Modarelli; Faculty reader, Matthew P. Espe; Department Chair, Kim C. Calvo; Dean of the College, Chand Midha; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.

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Fashina, Adedayo, Edith Amuhaya, and Tebello Nyokong. "Photophysical studies of newly derivatized mono substituted phthalocyanines grafted onto silica nanoparticles via click chemistry." Elsevier, 2015. http://hdl.handle.net/10962/d1020287.

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This work reports on the synthesis, characterization and photophysical studies of newly derived phthalocyanine complexes and the phthalocyanine–silica nanoparticles conjugates. The derived phthalocyanine complexes have one terminal alkyne group. The derived phthalocyanine complexes showed improved photophysical properties (ФF, ФT, ΦΔ and τT) compared to the respective phthalocyanine complexes from which they were derived. The derived phthalocyanine complexes were conjugated to the surface of an azide functionalized silica nanoparticles via copper (1) catalyzed cyclo-addition reaction. All the conjugates showed lower triplet quantum yields ranging from 0.37 to 0.44 compared to the free phthalocyanine complexes. The triplet lifetimes ranged from 352 to 484 μs for the conjugates and from 341 to 366 μs for the free phthalocyanine complexes.

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Adhikari, Ravi M. "Carbazole-Based Emitting Compounds: Synthesis, Photophysical Properties and Formation of Nanoparticles." Bowling Green State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1224527666.

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Ying, Hu. "Synthesis and Photophysical Properties of 3D Substituted Heterohelicenes and their Derivatives." Bowling Green State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1224602780.

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Rajapakse, Garusinghe Nepali. "Photophysical Properties of Metallotetraphenyltetrabenzoporphyrins: Insights From Experimental and Theoretical Studies." Bowling Green State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1213973075.

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Dong, Yujie. "Synthesis, photophysical properties and applications of aggregation-induced emission materials based on cyanostilbene moiety." HKBU Institutional Repository, 2016. https://repository.hkbu.edu.hk/etd_oa/313.

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The concept of "aggregation-induced emission" (AIE) effect has induced a great deal of attention these days. Now, exploration of new AIE-active molecular system and multiple high technique applications for AIE materials are the two research hotspots. Cyanostilbene, as a classical structural unit in photoelectric functional materials, also exhibited this unique luminescence behavior. The research background was illustrated in Chapter 1, which mainly introduced the development of this subject. In this project, Chapter 2 and Chapter 3 presented two classes of functionalized AIE-active molecules based on cyanostilbene moiety, and their applications were investigated, while Chapter 4 demonstrated a series of donor-acceptor (D-A) molecules with highly emissive unit, and their photophysical properties were studied.;In Chapter 2, four different donor-substituted cyanostilbene-based dipyrrins were synthesized and characterized. The investigation of photophysical properties confirms that these molecules are AIE-active, which should be attributed to the cyanostilbene moiety. The introduction of different donor groups showed little impact on their luminescence. Furthermore, the emission properties of these molecules were found to be sensitive to Zn2+, that is, addition of Zn2+ enormously enhanced its fluorescence in THF. The titration experiments proved they showed good selectivity and sensitivity for Zn2+ detection with relatively low limit of detection. Job's curve and spectral studies of their corresponding zinc complex indicated that the ratio for dipyrrins and Zn2+ is 2:1, which suggested the formation of zinc complex by chelation-enhanced fluorescence (CHEF) effect should be the reason of the enhanced fluorescence. By combining dipyrrin with typical AIE-active moiety tetraphenylethylene (TPE), an AIE-active TPE-based dipyrrin was prepared. The studies of its fluorogenic Zn2+ detection confirmed that the CHEF effect together with AIE effect are responsible for the intense fluorescence, indicating the potential application as a Zn2+ detector in aqueous media.;In Chapter 3, the cyanostilbene backbone was functionalized with a terpyridine unit to construct four terpyridine-based cyanostilbene molecules with different donor substitutents. The investigation of their photophysical properties confirms that they are AIEE-active. With the effect of different electron-donating groups, their solid-state fluorescence color was adjusted from blue to orange-red successfully. According to the calculation results of their frontier molecular orbitals, terpyridine has little impacts on their luminescence, but would influence their solid-state emission obviously owing to its large steric hindrance. This class of molecules displayed higher luminescence efficiency in solid state than in their dissolved state. The twisted molecular conformation in single crystal, which effectively avoids close π-π stacking, was assumed to be responsible for the high luminescence efficiency in solid state. This kind of molecules show distinct switched fluorescence by stimuli of acid/base vapors, and this phenomenon derives from the protonation effect of nitrogen atoms in the terpyridine unit. Moreover, three of these molecules exhibit good electroluminescence properties. Especially, the crystal of non-donor substituted molecule show amplified spontaneous emission (ASE) properties, indicating this blue-emissive material can be used in multiple areas such as chemical sensor, organic light emitting diodes (OLEDs) and organic laser media.

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Phillips, Sarah F. "A Photophysical Characterization on the Unique Properties of Perylene-3,4:9,10-bis((3,4,5(tris(oxtyloxy)benzohydrazide)-dicarboximide." University of Akron / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=akron1249081748.

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Payton, John L. PhD. "The Photophysical Behavior of Aryl-diphosphenes and Aryl-phosphaalkenes: A Theoretical Study." Cleveland, Ohio : Case Western Reserve University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=case1270488297.

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Thesis (Doctor of Philosophy)--Case Western Reserve University, 2010
Department of Chemistry Title from PDF (viewed on 2010-05-25) Includes abstract Includes bibliographical references and appendices Available online via the OhioLINK ETD Center

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Spilker, Thomas F. "DEVELOPMENT OF METAL-METAL QUADRUPLY BONDED COMPLEXES WITH π-EXTENDED STRUCTURES: SYNTHESIS, CHARACTERIZATION, PHOTOPHYSICAL PROPERTIES AND APPLICATIONS AS MOLECULAR SYNTHONS." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1405941090.

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Smith, Timothy J. "Synthesis and Photophysical Characterization of Covalent and Self-Assembled Oligo (Phenylenevinylenes) and Related Multichromophore-Containing Assemblies." Akron, OH : University of Akron, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=akron1249143659.

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Thesis (Ph. D.)--University of Akron, Dept. of Chemistry, 2009.
"August, 2009." Title from electronic dissertation title page (viewed 9/16/2009). Advisor, David A. Modarelli; Committee members, Matthew Espe, Michael Taschner, Yi Pang, Mukerrem Cakmak; Department Chair, Kim Calvo; Dean of the College, Chand Midha; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.

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Dzaye, Irene Yayra. "The Contribution of Charge Separation in Triplet State Formation in Zinc Dipyrrin Photosensitizers." Digital Commons @ East Tennessee State University, 2020. https://dc.etsu.edu/asrf/2020/presentations/34.

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About 85% of the world’s energy is derived from non-renewable sources—coal, petroleum, and natural gas. Solar photocatalysis is one way to potentially generate renewable fuels. Zinc dipyrrin complexes have the potential to be efficient sensitizers for reductive photochemistry, but their ability to form long-lived triplet excited states needs further investigation. The overall aim of this research is to compare the photophysical properties zinc and boron dipyrrin complexes and investigate the role of the charge separated state in triplet state formation. This presentation will describe the synthesis and purification of zinc and boron dipyrrin complexes and their photophysical characterization, including fluorescence quantum yields in a series of solvents and their emission at low temperatures.

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Sun, Yujie. "Ru(II) and Os(II) Polypyridyl Complexes as Luminescence Sensors and PDT Agents." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1279227020.

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Farshbaf, Sepideh. "Photophysical Studies of Luminescent Supra-Molecules and Their Application in Sensing of Anionic Analytes." Bowling Green State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1626352646326308.

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Budkina, Darya S. "Ultrafast photophysical and photochemical dynamics of polyhalogenated alkanes, cycloalkanes, and transition metal complexes." Bowling Green State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1553686775405944.

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Knittle, James Eugene. "Bioanalytical and photophysical applications of sensitive nonlinear wave-mixing spectroscopy based on laser-induced gratings /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2004. http://wwwlib.umi.com/cr/ucsd/fullcit?p3138952.

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Rubio, Pons Oscar. "Charge-transfer excitations and phtophysical properties of molecular building blocks." Doctoral thesis, KTH, Teoretisk kemi (stängd 20110512), 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-184.

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This thesis reports a state-of-the-art theoretical study of photophysical properties of organic charge-transfer aromatic molecules. These molecules are building blocks of molecular functional materials used in modern photonics technology and play essential roles in chemistry and biology in general. A good understanding of these systems is thus important. The theoretical results for permanent dipole moments of some substituted benzenes have been obtained using the coupled cluster singles and doubles (CCSD) method. The performance of density functional theory (DFT) for the geometry and electronic properties has been compared with that of traditional ab initio methods, such as Hartree-Fock, second-order Möller Plesset perturbation theory (MP2), CCSD and CCSD(T). Limitations of the DFT methods for charge transfer molecules have been demonstrated. The multi-configuration self-consistent field (MCSCF) method has been applied to understand properties of the triplet states of benzene derivatives by studying their phosphorescence with the inclusion of contributions from vibronic coupling. It has also been employed to calculate the photophysics of the thioxanthone molecule containing three benzene rings in combination with the CASPT2 method, resolving a long-standing problem concerning the possible stable conformations of the molecule. With knowledge of the building blocks a series of porphyrin derivatives with exceptionally large two-photon absorption cross sections were designed, and proposed for use in bioimaging applications. The static and dynamic properties of a few zinc and platinum organometallic compounds, being possible candidates for optical limiting devices, have also investigated.
QC 20101011

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Reed, Carly R. "The Photophysical Properties of Multiply Bonded Metal Complexes of Molybdenum, Tungsten, and Rhenium." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1309880937.

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Dollberg, Christopher L. "Zinc and ruthenium quinone diimine complexes: synthesis and photophysical properties." The Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=osu1071171484.

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Chakraborty, Arnab. "Design, Synthesis, Photophysical, and Electrochemical Studies of Novel Cyclometalated Pyrazolate-Bridged Dinuclear Platinum(II) Complexes." Bowling Green State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1395051194.

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Romano, Natalie C. "Photophysical Properties of Amphiphilic Naphthalene Diimide Nanoassemblies and Cadmium Sulfide Nanoparticles and Poly(phenylene-ethynylene) Nanocomposites." University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1399035654.

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48

Joseph, Jojo. "Photophysical Characterization of a Series of Self-Assembled Donor-Acceptor Dyads Containing Porphyrin and N-Confused Porphyrin Electron Donors and Studies of the Tautomerization of N-Confused Porphyrins." University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1376062678.

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Davies, Graham M. "The coordination chemistry of functionalised poly(pyrazol-1-yl)borate ligands and the photophysical properties of cyanide-bridged d-f hybrids." Thesis, University of Sheffield, 2006. http://etheses.whiterose.ac.uk/3584/.

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The content of this thesis is concerned with two distinctly independent areas of research: (i) the synthesis and study of new poly(pyrazol-1-yl)borate ligands and their metal complexes; (ii) crystallographic and photophysical studies of new d-f hybrid complexes. Chapter One is divided into three parts: Part one gives a general introduction to poly(pyrazol-1-yl)borate chemistry along with a concise and up-to-date review of those ligands containing substituents in the C3 position of the pyrazolyl ring; part two provides a brief introduction into the physical properties of lanthanide(III) metal ions, as well as describing the practical applications of their individual spectroscopic properties; and part three contains a brief review on the structural chemistry of cyanide-bridged coordination polymers. Chapter Two describes the syntheses of four new scorpionates: dihydrobis[3-(4-pyridyl)pyrazol-1-yl]borate (Bp4py); dihydro-bis[3-(3-pyridyl)pyrazol-1- yl]borate (Bp3py); hydro-tris[3-(4-pyridyl)pyrazol-1-yl]borate (Tp4py) and hydrotris[3-(3-pyridyl)pyrazol-1-yl]borate (Tp3py). A series of X-ray crystallographic studies reveals a range of mononuclear, dinuclear and polymeric coordination complexes with various metal ions. Chapter Three describes a range of structural and photophysical studies on lanthanide(III) complexes of poly(pyrazol-1-yl)borate ligands. New mixed-ligand lanthanide(III) complexes with various combinations of the anionic ligands Tp2py , Bp2py and dibenzoylmethane (dbm) were prepared and structurally characterised. Photophysical studies on the isostructual series [Ln(Bp2py)(dbm)2] (Ln = Pr, Nd, Er, Yb) show characteristic near-IR luminescence from the lanthanide ion. Near-IR luminescence was also demonstrated from the complexes [Ln(Bp2py) 2(NO3)] and [Ln(Tp2py)(NO3) 2] (Ln = Pr, Er), upon suitable excitation of the ligand chromophores. Chapter Four describes the structural and photophysical properties of new cyanide-bridged d-f coordination polymers. Structural and photophysical studies are presented for a series of Ru-Ln complexes based on the [Ru(bipy)(CN)4] 2- donor unit connected to a Ln(III) energy-acceptor via cyanide bridges (where bipy is 2,2’- bipyridine and Ln = Pr, Nd, Er, Yb). Structural and photophysical studies were also performed on [Cr(CN)6][Ln(DMF)4(H2 O)2] complexes, in which the lanthanide ion (Ln = Nd, Yb) acts as the energy acceptor from the hexacyanochromate chromophore. The structures of [Cr(CN)6][Ln(H2 O)2] (Ln = Gd, Yb) and K2[Ru(phen)(CN)4] (where phen = 1,10-phenanthroline) are also presented. Chapter Five gives a brief review of the field of X-Ray Crystallography with analysis of the history and theory of the technique, as well as an overview of its practical aspects used in this work. A few crystal structures solved by the author, and independent of the topics in this thesis, are also reported.

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Maddipatla, Venkata Srirama Narasimha Murthy. "Influence of Confined Media on Photophysical and Photochemical Transformations of Organic Guest Molecules: Water Soluble Supramolecules as Confined Media." Scholarly Repository, 2009. http://scholarlyrepository.miami.edu/oa_dissertations/192.

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For more than 150 years, since the synthesis of urea by Friedrich Wöhler in 1828, molecular chemistry has developed a vast array of highly sophisticated and powerful methods for the construction of more complex molecular structures. Beyond the molecular chemistry based on the covalent bond, there lies the field of supramolecular chemistry, aims to gain control over the intermolecular bond. Supramolecular species are characterized both by the spatial arrangement of their components and by the nature of the intermolecular bonds that hold these components together. They possess well-defined structural, conformational, thermodynamic and kinetic properties. Research has been focused on utilization of such confined spaces to manipulate reaction dynamics, properties of the encapsulated guest molecules. This research presented in this thesis is a consolidated account of photophysical and photochemical reactions carried in water-soluble macrocycles, cavitands and dynamic host systems such as dendrimers and micelles. With the aid of NMR (1D and 2D) spectroscopic techniques, the host-guest complex characterization is executed.

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Dissertations / Theses on the topic 'Photophysical Chemistry'

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