Read Books Online and Download eBooks, EPub, PDF, Mobi, Kindle, Text Full Free.
Synthesis And Excited State Dynamics Of Strongly Luminescent Goldiii And Goldi Complexes With Long Lived Excited States
Download Synthesis And Excited State Dynamics Of Strongly Luminescent Goldiii And Goldi Complexes With Long Lived Excited States full books in PDF, epub, and Kindle. Read online Synthesis And Excited State Dynamics Of Strongly Luminescent Goldiii And Goldi Complexes With Long Lived Excited States ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis Synthesis and Excited State Dynamics of Strongly Luminescent Gold(III) and Gold(I) Complexes with Long-lived Excited States by : 陳玠彤
Download or read book Synthesis and Excited State Dynamics of Strongly Luminescent Gold(III) and Gold(I) Complexes with Long-lived Excited States written by 陳玠彤 and published by . This book was released on 2016 with total page 626 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis DESIGN & SYNTHESIS OF LUMINESC by : Suk-Hang Lam
Download or read book DESIGN & SYNTHESIS OF LUMINESC written by Suk-Hang Lam and published by Open Dissertation Press. This book was released on 2017-01-26 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Design and Synthesis of Luminescent Platinum(II) and Gold(III) Complexes With Tridentate Pincer-type Ligands: From Computational Study to Experiments and Application Studies" by Suk-hang, Lam, 林淑恒, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled DESIGN AND SYNTHESIS OF LUMINESCENT PLATINUM(II) AND GOLD(III) COMPLEXES WITH TRIDENTATE PINCER-TYPE LIGANDS - FROM COMPUTATIONAL STUDY TO EXPERIMENTS AND APPLICATION STUDIES Submitted by LAM Suk Hang for the degree of Doctor of Philosophy at The University of Hong Kong in June 2015 Square planar platinum(II) and gold(III) complexes possess unique spectroscopic and photophysical properties which enable them as promising candidates for many applications such as optoelectronic devices and biological sensors. The understanding of the intrinsic properties of these complexes is therefore essential to optimize their performance as well as provide guidance on the molecular design for specific applications. This thesis aims to provide useful insights for the molecular design strategies with the aid of computational studies to tune the electronic properties of these complexes and electroluminescence studies in the fabrication of organic light-emitting devices (OLEDs). Computational studies have been performed to inspect electronic structures and photophysical properties as well as their correlation with the nature of ancillary ligands in the platinum(II) complexes of 1,3-bis(N-alkylbenzimidazol-2′-yl)benzene, [Pt(bzimb)(C≡C-R)], 1,3-bis-hetero-azolylbenzenes, [Pt(N DEGREESC DEGREESN)(C≡C-R)], and pyridine-based N-heterocyclic carbene, [Pt(NHC)(C≡C-R)] . It was found that the emission of the arylalkynylplatinum(II) complexes with pyridine-based N-heterocyclic carbene ligand was originated from the triplet alkynyl-to-tridentate pincer ligand-to-ligand charge transfer excited state mixed with platinum-to-tridentate pincer metal-to-ligand charge transfer character, and the excited state energy was found to be red-shifted according to the increasing π electron-donating ability of the aryl group attached to the alkynyl ligand. On the other hand, the emission energies of the platinum(II) complexes of 1,3-bis(N-alkylbenzimidazol-2′-yl)benzene and 1,3-bis-hetero-azolylbenzenes were found to be dependent on the different electron-donating substituents on the pincer ligands. Calculations have also been performed on the representative alkynylplatinum(II) + + complexes [Pt(trpy)(C≡C-R)] (trpy = 2,2′ 6′,2′′-terpyridine), [Pt(bzimpy)(C≡C-R)] (bzimpy = 2,6-bis(N-alkylbenzimidazol-2′-yl)pyridine) and [Pt(bzimb)(C≡C-R)] as well as alkynylgold(III) complexes [Au(C DEGREESN DEGREESC)(C≡C-R)] (C DEGREESN DEGREESC = 2,6-diphenylpyridine), [Au{C(Np) DEGREESN DEGREESC(Np)}(C≡C-R)] (C(Np) DEGREESN DEGREESC(Np) = 2,6-di(2-naphthyl)pyridine) and [Au(N DEGREESN DEGREESN)(C≡C-R)] (N DEGREESN DEGREESN = 2,6-bis(1H-benzimidazol-2-yl)pyridine) in order to have a better understanding on their nature of the emissive origins as well as the radiative and nonradiative processes. In particular, factors governing the ordering of the triplet excited states and radiative decay rate constants of the emissive state ( ES) have been examined. Their potential energy profiles for the deactivation process from the ES via triplet metal-centered states have also been explored. This study revealed for the first time the potential energy profiles for the thermal deactivation pathway of square planar platinum(II) and gold(III) complexes. In addition to the computational
Book Synopsis Novel Luminescent Cyclometalated Gold (III) Alkynyls by : Ling-Ling Hung
Download or read book Novel Luminescent Cyclometalated Gold (III) Alkynyls written by Ling-Ling Hung and published by Open Dissertation Press. This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Novel Luminescent Cyclometalated Gold (III) Alkynyls: Design, Synthesis, Photophysics and Their Multinuclear Assemblies" by Ling-ling, Hung, 熊靈玲, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled NOVEL LUMINESCENT CYCLOMETALATED GOLD(III) ALKYNYLS - DESIGN, SYNTHESIS, PHOTOPHYSICS AND THEIR MULTINUCLEAR ASSEMBLIES Submitted by HUNG Ling Ling for the Degree of Doctor of Philosophy at The University of Hong Kong in November 2007 A new class of luminescent mononuclear cyclometalated gold(III) complexes containing various monoynyl ligands, [Au(RC DEGREESN(R′) DEGREESCR)(C≡CR′′)], i.e. [Au(C DEGREESN DEGREESC)(C≡CR′′)] (HC DEGREESN DEGREESCH = 2,6-diphenylpyridine; R′′ = C H, C H-Cl-p, 6 5 6 4 C H-C H -p, C H-OCH -p, C H-NO -p, C H-NH -p, C H-N(CH ) -p, 6 4 6 13 6 4 3 6 4 2 6 4 2 6 4 3 2 t t t t C H-N(C H ) -p, C H ), [Au( BuC DEGREESN DEGREESC Bu)(C≡CR′′)] (H BuC DEGREESN DEGREESCBuH = 2,6- 6 4 6 5 2 6 13 bis(4-tert-butylphenyl)pyridine; R′′ = C H, C H-NH -p, Si(CH ), H), 6 5 6 4 2 3 3 [Au(FC DEGREESN DEGREESCF)(C≡CR′′)] (HFC DEGREESN DEGREESCFH = 2,6-bis(4-fluorophenyl)pyridine; R′′ = C H, 6 5 C H-NH -p) and [Au(C DEGREESNTol DEGREESC)(C≡CC H-C H -p)] (HC DEGREESNTol DEGREESCH = 2,6- 6 4 2 6 4 6 13 diphenyl-4-p-tolylpyridine) have been synthesized. Most of the complexes have been structurally determined by X-ray crystallography which revealed the presence of intermolecular π-π stacking interaction with interplanar separations between [Au(RC DEGREESN(R′) DEGREESCR)] units of ca. 3.343-3.570 A. The lowest-lying excited states of 3 these complexes in dichloromethane were assigned as the metal-perturbed IL [π → π*(RC DEGREESN(R′) DEGREESCR)] origin, with substantial charge transfer character from the aryl ring to the pyridyl unit, whereas a switch in the lowest-lying excited states origin to LLCT [π(C≡CC H NR′′′ ) → π*(RC DEGREESN(R′) DEGREESCR)] was observed in complexes 6 4 2 containing aminophenyl alkynyl ligands. The low-energy emissions in the solid state were attributed to the π-π excimeric intraligand phosphorescence, arising from the intermolecular π-π stacking interactions of the RC DEGREESN(R′) DEGREESCR ligands in the solid state as revealed from the crystal packing diagrams. A series of luminescent mononuclear cyclometalated gold(III) complexes with various oligoynyl ligands, [Au(RC DEGREESN DEGREESCR)(C≡CR′)] (R = H, R′ = C≡CH, C H-C≡CH, C≡CC H, C≡CC H-CH -p, C≡CC H-CF -p, C≡CC H-NH -p, 6 4 6 5 6 4 3 6 4 3 6 4 2 C≡C-C≡CC H; R = Bu, R′ = C≡CH, C H-C≡CH) have also been synthesized. 6 5 6 4 The di- and trinuclear cyclometalated gold(III) alkynyl complexes, [1,4- t t t t {Au( BuC DEGREESN DEGREESC Bu)C≡C} C H ] and [1,3,5-{Au( BuC DEGREESN DEGREESC Bu)C≡C} C H ], have also 2 6 4 3 6 3 been prepared. The X-ray crystal structures of [Au(RC DEGREESN DEGREESCR)(C≡CR′)] (R = H, R′ = C≡CH, C H-C≡CH, C≡CC H-CH -p, C≡CC H-CF -p; R = Bu, R′ = 6 4 6 4 3 6 4 3 t t C H-C≡CH) and [1,3,5-{Au( BuC DEGREESN DEGREESC Bu)C≡C} C H ] have been determined. The 6 4 3 6 3 t t molecular structure of [1,3,5-{Au( BuC DEGREESN DEGREESC Bu)C≡C} C H ] showed the twisting of 3 6 3 t t the three coordination planes, [Au( BuC DEGREESN DEGREESCBu)], relative to the central phenyl ring with dihedral angles of 6.1, 48.4 and 60.7. Similarly, the emissions of most of the complexes in fluid solution were attributed to the metal-perturbed IL [π → π*(RC DEGREESN DEGREESCR)] phosphorescence with substantial charge transfer character from the aryl group to the pyridyl unit, while the emission origin was assigned as derived 3 f
Book Synopsis Synthesis and Characterization of Luminescent Gold(III) Complexes by : Amanda N. Sulicz
Download or read book Synthesis and Characterization of Luminescent Gold(III) Complexes written by Amanda N. Sulicz and published by . This book was released on 2017 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: The chemistry of cyclometalated gold(III) has been relatively slow to emerge, but recent advances in catalyst and material design have driven a renewed interest. Reported here are synthetic, structural, and optical studies of cyclometalated gold(III) aryl complexes. These new complexes show ligand-centered luminescence that is perturbed by the heavy-atom effect of gold. Traditionally, metal-carbon bond formation relied on organometallic complexes of electropositive elements, including lithium and magnesium. The easily reducible nature of gold(III) often interferes with these conventional reagents, thus resulting in the use of toxic metals like mercury or thallium. Reported here is the use of palladium-catalyzed Suzuki-Miyaura cross-coupling for the attachment of aryl ligands to cyclometalated gold(III) chloride complexes. The resulting di- and mono-arylated species were luminescent. Several complexes have been crystallographically characterized. Luminescent derivatives of a previously published gold(III) chloro precursor, initially reported for catalytic purposes, were prepared through boron transmetalation reactions. Complexes bearing both aryl and cyanide ligands were synthesized. These luminescent materials are diamagnetic and were be characterized by multinuclear NMR, absorption and emission spectroscopies (including time-resolved emission), and by X-ray diffraction crystallography. The synthesized gold(I) complexes were designed to display reverse saturable absorption and be a two photon acceptor. The BTF (BTF = 2-(9,9’-diethyl-9H-fluoren-2-yl)-benzothiazole) ligand was chosen as it has been previously demonstrated to have favorable photophysical effects on platinum(II) and ruthenium(II) complexes for applications in photodynamic therapy and optical power limiting (OPL). Gold(I) complexes with the BTF ligand are sought for potential OPL applications. Synthesized complexes are luminescent and were characterized by multinuclear NMR, absorption and emission spectroscopies, photoluminescent quantum yields, time-resolved emission. Two complexes were crystallographically characterized.
Book Synopsis Luminescent Dinuclear D8 Gold(III) and Platinum(II) Complexes by : 盧嘉偉
Download or read book Luminescent Dinuclear D8 Gold(III) and Platinum(II) Complexes written by 盧嘉偉 and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Chemical and Biological Generation of Excited States by : Waldemar Adam
Download or read book Chemical and Biological Generation of Excited States written by Waldemar Adam and published by . This book was released on 1982 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chemical and Biological Generation of Excited States discusses major aspects of chemical and biological generation of electronic excitation. This book is organized into 11 chapters that focus on both chemi- and bioenergized processes. This book first discusses some of the fundamental aspects of the description of excited state behavior in condensed media. It then examines the field of gas-phase dioxetane chemiluminescence both by itself and in relation to solution-phase studies. The presented analysis is based on statistical mechanics and supported by a very simple limiting case calculation. C ...
Book Synopsis Synthesis, Crystallization, and Characterization of Gold(I) Complexes with Studies on Luminescence, Polymorphism, and Response to Environmental Stimuli by : Phuong (Lucy) Minh Cam Luong
Download or read book Synthesis, Crystallization, and Characterization of Gold(I) Complexes with Studies on Luminescence, Polymorphism, and Response to Environmental Stimuli written by Phuong (Lucy) Minh Cam Luong and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The research presented in this dissertation focuses on the synthesis, crystallization, and characterization of various gold(I) complexes. With every gold(I) crystal, intensive studies were conducted to uncover any luminescence, polymorphism, and/or response to environmental stimuli such as temperature, vapor, and pressure. All doctoral research performed in the Balch lab, including collaborations with other members as well as outside research groups, is not fully presented in this dissertation. A list of publications can be found at the end. Chapter 1 explores the role of anions and mixture of anions in crystals of bis(cyclohexylioscyanide) gold(I) cations, [(C6H11NC)2Au]+. A new crystal was synthesized and characterized with the (SbF6)− noncoordinating anion. The crystal displayed no known polymorphism unlike its previously synthesized (PF6)− and (AsF6)− analogues. However, by mixing combinations of anions and ratios of anions, an isostructural set of crystals were produced. Not only were thermochromic trends observed for mixed anion crystals with known thermochromic species but unexpected thermochromic properties appeared in mixed anion crystals that contained species with no thermochromism. In Chapter 2, the vapochromic and vapoluminescent properties of both [(C6H11NC)2Au](PF6) and [(C6H11NC)2Au](AsF6) were further investigated to uncover the first observed single-crystal-to-single-crystal phase transition, verified by single crystal X-ray diffraction, of both species. A rare case of a two-polymorph single crystal of each species was achieved as well. With no vapor molecules incorporated in these crystals, the mechanism of conversion was further examined at the macroscopic, microscopic, and atomic level to understand how these solvent-free crystals transform from solvent vapor exposure. Chapter 3 focuses on methods to isolate [(C6H11NC)2Au]+ to form non-luminescent crystals, which was achieved through bulky noncoordinating anions and solvent molecules. Newly synthesized [(C6H11NC)2Au](BArF24) was crystallized but showed no further interesting properties other than purposely isolating aurophilic interactions. However, the first solvates of these [(C6H11NC)2Au]+ series, C6H6·[(C6H11NC)2Au](AsF6) and C6H6·[(C6H11NC)2Au](SbF6), were crystallized that displayed a unique turning on of luminescence when left to dry that matched their solvent-free forms, as verified by powder X-ray diffraction, infrared spectroscopy, and fluorescence spectroscopy. Differing from the other studies, Chapter 4 examines the structure and luminescence of three-coordinate 2,2'-bipyridine gold(I) tertiary phosphine crystals. Separate isomorphic series of [(Ph3P)Au(bipy)]XF6 and [(Et3P)Au(bipy)]XF6 (where X = P, As, or Sb) along with binuclear [[mu]2-bipy(AuPPh3)2](PF6)2 were crystallized and showed no luminescence, which is unlike that of known strongly luminescent gold(I) phosphines. However, the three-coordinate [(Ph3P)Au(bipy)]XF6 and [(Et3P)Au(bipy)]XF6 complexes all displayed significantly unsymmetrical coordination of the gold(I) to the two nitrogen atoms in the 2,2'-bipyridine ligand. These large unsymmetrical distances were further investigated.
Book Synopsis Iridium(III) in Optoelectronic and Photonics Applications by : Eli Zysman-Colman
Download or read book Iridium(III) in Optoelectronic and Photonics Applications written by Eli Zysman-Colman and published by John Wiley & Sons. This book was released on 2017-03-07 with total page 736 pages. Available in PDF, EPUB and Kindle. Book excerpt: The fundamental photophysical properties of iridium(III) materials make this class of materials the pre-eminent transition metal complex for use in optoelectronic applications. Iridium(III) in Optoelectronic and Photonics Applications represents the definitive account of photoactive iridium complexes and their use across a wide variety of applications. This two-volume set begins with an overview of the synthesis of these complexes and discusses their photophysical properties. The text highlights not only mononuclear complexes but also the properties of multinuclear and polymeric iridium-based materials and the assembly of iridium complexes into larger supramolecular architectures such as MOFs and soft materials. Chapters devoted to the use of these iridium-based materials in diverse optoelectronic applications follow, including: electroluminescent devices such as organic light emitting diodes (OLEDs) and light-emitting electrochemical cells (LEECs); electrochemiluminescence (ECL); bioimaging; sensing; light harvesting in the context of solar cell applications; in photoredox catalysis and as components for solar fuels. Although primarily targeting a chemistry audience, the wide applicability of these compounds transcends traditional disciplines, making this text also of use to physicists, materials scientists or biologists who have interests in these areas.
Book Synopsis Highly Efficient OLEDs with Phosphorescent Materials by : Hartmut Yersin
Download or read book Highly Efficient OLEDs with Phosphorescent Materials written by Hartmut Yersin and published by John Wiley & Sons. This book was released on 2008-06-25 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt: This monograph on organic light emitting diodes, edited by a pioneer, and written by front-line researchers from academia and industry, provides access to the latest findings in this rapidly growing field. More than ten contributions cover all areas -- from theory and basic principles, to different emitter materials and applications in production.
Book Synopsis Design, Synthesis and Functionalization of Stimuli-responsive Luminescent Gold(i) Alkynyl, Chalcogenido and Phosphinidene Complexes by : 朱劼怡
Download or read book Design, Synthesis and Functionalization of Stimuli-responsive Luminescent Gold(i) Alkynyl, Chalcogenido and Phosphinidene Complexes written by 朱劼怡 and published by . This book was released on 2019 with total page 367 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Modern Supramolecular Gold Chemistry by : Antonio Laguna
Download or read book Modern Supramolecular Gold Chemistry written by Antonio Laguna and published by John Wiley & Sons. This book was released on 2008-09-26 with total page 525 pages. Available in PDF, EPUB and Kindle. Book excerpt: Filling a gap in our systematic knowledge of gold, this monograph covers the fundamental aspects, while also considering new applications of gold compounds in catalysis, as nanoparticles, and their potential application as luminescent compounds. Written by an eminent team of authors from academia, the book analyzes the current status of gold chemistry, its special characteristics, oxidation states and main type of complexes, before going on to look at the synthesis of supramolecular aggregates due to the formation of gold-gold, gold-metal interactions or other secondary bonds. Final sections deal with LEDs, solvoluminescent and electroluminescent materials, liquid crystals and catalysis. While of interest to advanced chemistry students, this book is also useful for researchers interested in the chemistry of gold and its applications, as well as those involved in metal-metal interactions, heteronuclear chemistry or in the optical properties of coordination compounds.
Book Synopsis Properties and Reactivities of the Luminescent Excited States of Polypyridine Complexes of Ruthenium(II) and Osmium(II). by :
Download or read book Properties and Reactivities of the Luminescent Excited States of Polypyridine Complexes of Ruthenium(II) and Osmium(II). written by and published by . This book was released on 1977 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The properties of the luminescent excited states of polypyridineruthenium(II) and -osmium(II) complexes (*ML/sub 3//sup 2 +/) are discussed in terms of the properties of the ML/sub 3//sup 2 +/, ML/sub 3//sup 3 +/, and ML/sub 3//sup +/ ground state species. Both *Ru(bpy)/sub 3//sup 2 +/ and *Os(bpy)/sub 3//sup 2 +/ exhibit spectral maxima at approximately 360 nm and 430-460 nm but the *OsL/sub 3//sup 2 +/ lifetimes (approximately 9 to 85 nsec) are much shorter than those for the corresponding *RuL/sub 3//sup 2 +/ species (330 to 1500 nsec). Excited state potentials for the complexes have been estimated from their spectra and ground state potentials, as well as from photocurrent measurements at an n-type TiO/sub 2/ electrode. The reactivity of *ML/sub 3//sup 2 +/ toward outer-sphere electron-transfer parallels that of ML/sub 3//sup 3 +/ when it undergoes reduction and that of ML/sub 3//sup +/ when it undergoes oxidation. Reactions between *ML/sub 3//sup 2 +/ and ground state polypyridinemetal(II) complexes give rise to electron-transfer (+1 and +3 ions) or to energy transfer products depending on the pair of complexes used.
Book Synopsis Radiationless Transitions by : Sheng Lin
Download or read book Radiationless Transitions written by Sheng Lin and published by Elsevier. This book was released on 2012-12-02 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt: Radiationless Transitions is a critical discussion of research studies on the theory and experiments in radiationless transitions. This book is composed of nine chapters, and begins with discussions on the theory and experiment of photophysical processes of single vibronic levels and/or single rovibronic levels. The subsequent chapters deal with the spectroscopic investigations of intramolecular vibrational relaxation; the dynamics of molecular excitation by light; and the photophysical processes of small molecules in condensed phase. The discussions then shift to the high pressure effects on molecular luminescence and the internal conversion involving localized excitations, presenting one qualitative and one quantitative example, as well as the intersystem crossing with localized excitations. A chapter explores the energy transfer processes that occur after a molecule in solution is excited by light, with an emphasis on solid solutions in which the large amplitude molecular motion is largely quenched. This chapter also looks into the liquid solutions in which the molecules can translate and rotate under the influence of fluctuating forces from the liquid. The concluding chapter focuses on ultrafast processes. Researchers in the fields of physics, chemistry, and biology will benefit from this book.
Book Synopsis Properties and Reactivities of the Luminescent Excited States of Polypyridine Complexes of Ruthenium(II) and Osmium(II) by :
Download or read book Properties and Reactivities of the Luminescent Excited States of Polypyridine Complexes of Ruthenium(II) and Osmium(II) written by and published by . This book was released on 1977 with total page 49 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis A New Class of Luminescent Organometallics-diethynylrhodacyclopentadienes by :
Download or read book A New Class of Luminescent Organometallics-diethynylrhodacyclopentadienes written by and published by . This book was released on 2010 with total page 263 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main objective in this project is to develop a greater understanding of the unusual photophysical properties of 2,5-bis(arylethynyl)rhodacyclopentadienes. Three distinct and unusual photophysical properties were found in the 2,5-bis(arylethynyl)- rhodacyclopentadienes: (i) long {u2013}lived singlet excited states, from which some of them exhibit high-intensity fluorescence with nanosecond lifetimes; (ii) slow intersystem crossing rates (k values 108 s-1) compared to typical luminescent organometallic complexes ( with k values 1012 s-1); and (iii) no phosphorescence was observed even at 77 k in a rigid glass. Many photophysical experiments such as e.g. low-temperature lifetime measurements, singlet oxygen sensitization and time-resolved infrared (TRIR) have been carried out in order to investigate further and explain the unusual photophysical properties of this class of organometallic complexes. The first example of isomeric biphenyl-rhodacyclopentadiene by-product formation was found in the synthesis of acac-rhodacyclopentadienes. The isomeric biphenylrhodacyclopentadiene by-product with R = CO2ME was isolated and its molecular structure was confirmed by x-ray analysis. Its emission spectrum shows two emission bands with max values of 394 and 544 nm in degassed toluene solution. The fluorescent emission at 394 nm has a quantum yield of 0.03, whereas the phosphorescent emission at 544 nm has a quantum yield of 0.05. The unusual long lifetime (237.6us) of the phosphorescence at room temperature indicates that the transition is from a ligandcentred (LC) * transition. In addition, the synthesis of 1,4-bis(p-R-phenyl) buta-1,3-diynes and novel 1,12-bis(p-R-phenyl)dodaca-1,3,9,11-tetraynes, which serve as the starting materials for the synthesis of the rhodacyclopentadienes, are also reported. Four novel 1,12-bis(p-R-phenyl)dodaca-1,3,9,11-tetraynes (where R = H, SMe, CO2Me and BMes2) have been synthesized and characterised.
Book Synopsis Photochemistry and Photophysics of Coordination Compounds by : Hartmut Yersin
Download or read book Photochemistry and Photophysics of Coordination Compounds written by Hartmut Yersin and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the Seventh International Symposium on the Photochemistry and Photophysics of Coordination Compounds Elmau/FRG, March 29-April 2, 1987
Book Synopsis Light-Emitting Electrochemical Cells by : Rubén D. Costa
Download or read book Light-Emitting Electrochemical Cells written by Rubén D. Costa and published by Springer. This book was released on 2017-07-31 with total page 371 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the recent achievements towards the next generation of Light-emitting electrochemical cells (LEC). Its first part focus on the definition, history and mechanism of LEC, going then to concepts and challenges and, finally, giving the reader examples of current application of new electroluminescent materials. The chapters are written by different international groups working on LEC.
