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Book Luminescent Platinum ii  Complexes Containing Dianionic Tetradentate Ligands Having Mixed Oxygen  Nitrogen and Carbon Donor Atoms and Platinum ii  Containing Phosphorescent Polymers

Download or read book Luminescent Platinum ii Complexes Containing Dianionic Tetradentate Ligands Having Mixed Oxygen Nitrogen and Carbon Donor Atoms and Platinum ii Containing Phosphorescent Polymers written by Wai-Yip Tong and published by Open Dissertation Press. This book was released on 2017-01-26 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Luminescent Platinum(II) Complexes Containing Dianionic Tetradentate Ligands Having Mixed Oxygen, Nitrogen and Carbon Donor Atoms and Platinum(II)-containing Phosphorescent Polymers: Synthesis, Photophysical Properties and Material Applications" by Wai-yip, Tong, 唐煒燁, 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 LUMINESCENT PLATINUM(II) COMPLEXES CONTAINING DIANIONIC TETRADENTATE LIGANDS HAVING MIXED OXYGEN, NITROGEN AND CARBON DONOR ATOMS AND PLATINUM(II)-CONTAINING PHOSPHORESCENT POLYMERS: SYNTHESIS, PHOTOPHYSICAL PROPERTIES AND MATERIAL APPLICATIONS Submitted by TONG WAI YIP for the degree of Doctor of Philosophy at The University of Hong Kong in May 2014 Square planar platinum(II) complexes exhibit rich photophysical properties which are tunable through the structural variation of ligands and can be harnessed for applications in materials science. In this thesis, the great variety of spectroscopic properties of various square planar cyclometalated platinum(II) complexes supported by tetradentate (O DEGREESN DEGREESN DEGREESC and O DEGREESN DEGREESC DEGREESN) and tridentate (C DEGREESN DEGREESN) ligands containing dipyridyl moieties will be highlighted, along with their synthesis, characterization and potential application in organic light emitting diodes (OLEDs). Ind Platinum(II) complexes supported by tetradentate O DEGREESN DEGREESN DEGREESC or O DEGREESN DEGREESN DEGREESC types of ligands (O DEGREESN DEGREESN DEGREESC = 2-(4-(3,5-di-tert-butylphenyl)-6'-phenyl-2,2'- Ind bipyridin-6-yl)phenolate; O DEGREESN DEGREESN DEGREESC = 5,5-dialkyl-2-(6-phenylpyridin-2-yl) indeno[1,2-b]pyridin-9-olate) are emissive in solution at room temperature, with emission maxima tunable from 582 nm to 640 nm and quantum yields up to 0.28. Mechanochromism and the associated luminescence change in [Pt(dihexyl- Ind O DEGREESN DEGREESN DEGREESC)] (Complex 3.6) were found associated with the two different crystal packings revealed by powder X-ray diffraction (PXRD) studies. Fast vapochromic response of [Pt(3-O DEGREESN DEGREESN-2,6-difluoropyridine)] (Complex 3.3) on chloroform or dichloromethane vapours was found to be associated with structural changes in the solid state through PXRD studies. Robust and strongly emissive platinum(II) complexes supported by tetradentate O DEGREESN DEGREESC DEGREESN ligands featuring fused six-five-six membered metallacyclic ring (O DEGREESN DEGREESC DEGREESN = 2-(4-(3,5-di-tert-butylphenyl)-6-(9-(pyridin-2-yl) carbazol-2-yl)pyridin-2-yl)phenol) have been prepared. These platinum(II) complexes are among the most efficient yellow phosphors, with emission maxima ranging from 526 nm to 553 nm and luminescence quantum yields as high as -1 0.47-0.86. A yellow OLED with power efficiency (η ) up to 52 lm W is power demonstrated. In combination with the typical blue emitting iridium(III) 2' bis(4,6-difluorophenyl-pyridinato-N, C ) picolinate (FIrpic), white organic -1 light-emitting diodes (WOLEDs) displayed η up to 61 lm W and reduced power -2 efficiency roll-off at 1000 cd m . Random copolymers with photo-inert backbone poly[(N-vinylcarbazole)-co- ((R-C DEGREESN DEGREESN)Pt)] and poly[(2-(4-tert-butylphenyl)-5-(4-vinylphenyl)-1,3,4- oxadiazole)-co-((R-C DEGREESN DEGREESN)Pt)] (R-C DEGREESN DEGREESN = 3-(6-phenyl-4-(4-vinylphenyl) pyridine-2-yl)-isoquinoline or 3-(4-(4-(dec-9-enyloxy)phenyl)-6-phenylpyridin- 2-yl)isoquinoline) have been synthesized and characterized. Energy transfer between the charge transporting units and emissive (R-C DEGREESN DEGREESN)Pt units was revealed through ICP-MS inve

Book Luminescent Platinum II  Complexes Containing Dianionic Tetradentate Ligands Having Mixed Oxygen  Nitrogen and Carbon Donor Atoms and Platinum II  containing Phosphorescent Polymers

Download or read book Luminescent Platinum II Complexes Containing Dianionic Tetradentate Ligands Having Mixed Oxygen Nitrogen and Carbon Donor Atoms and Platinum II containing Phosphorescent Polymers written by 唐煒燁 and published by . This book was released on 2014 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Luminescent Tetradentate Platinum II  Complexes Bearing Asymmetric Ligands with Mixed Oxygen  Nitrogen and Carbon Donor Atoms

Download or read book Luminescent Tetradentate Platinum II Complexes Bearing Asymmetric Ligands with Mixed Oxygen Nitrogen and Carbon Donor Atoms written by 高敏盈 and published by . This book was released on 2017 with total page 411 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book LUMINESCENT PALLADIUM II    PL

    Book Details:
  • Author : Pui-Keong Chow
  • Publisher : Open Dissertation Press
  • Release : 2017-01-26
  • ISBN : 9781361005378
  • Pages : 502 pages

Download or read book LUMINESCENT PALLADIUM II PL written by Pui-Keong Chow and published by Open Dissertation Press. This book was released on 2017-01-26 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Luminescent Palladium(II) and Platinum(II) Complexes With Tridentate Monoanionic and Tetradentate Dianionic Cyclometallated Ligands: Structures, Photophysical Properties and Material Application" by Pui-keong, Chow, 周沛強, 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: Four structural isomers of platinum(II) complexes with C-deprotonated R-C DEGREESN DEGREESN-R' cyclometallated ligands (R-C DEGREESN DEGREESN-R' = -extended 6-aryl-2,2'-bipyridine derivatives containing 2-naphthyl, 3-isoquinolinyl, 1-isoquinolinyl or 2-quinolinyl moieties) have been synthesized with their photophysical properties investigated. The one bearing a 3-isoquinolinyl moiety shows the highest emission quantum yield among the four and hence has been extensively modified to give a series of complexes with different ancillary ligands (chloride, iodide, phenoxide, or acetylide). Most of these complexes show vibronic emission (max = 515-644 nm) with high emission quantum yield (up to unity) in degassed CH2Cl2; one of them has been used for OLED fabrication and shows a maximum EQE of 8.15 % with current efficiency of 25 cd A-1. The photocatalytic properties of these derivative complexes for oxidative tertiary amine functionalization have also been examined. Several highly robust and emissive platinum(II) complexes supported by two types of tetradentate O DEGREESN DEGREESC DEGREESN ligand systems (Φem up to 0.99; Td up to 520 ℃) have been synthesized and show different emission energies (λmax = 482-561 nm). Most of them exhibit excimeric emission in solution state at room temperature which are dependent on the modifications on the tetradentate O DEGREESN DEGREESC DEGREESN ligands. DFT/TDDFT calculations reveal that the metal complex showing the most intense excimeric emission possesses an excimeric excited state with a localized structure, which is unusual for these classes of platinum(II) complexes. Based on this finding, WOLED (ηL(max) = 71.0 cd/A, ηp(max) = 55.8 lm/W, ηExt = 16.5 %, CIE = 0.33, 0.42, CRI = 77) and WPLED (ηL(max) = 17.0 cd/A, ηp(max) = 9.1 lm/W, ηExt = 9.7 %, CIE = 0.43, 0.45, CRI = 78) based on this complex have been fabricated with high efficiency achieved. Palladium(II) complexes containing C-deprotonated R-C DEGREESN DEGREESN-R' cyclometallated and pentafluorophenylacetylide ligands exhibit phosphorescence in both solid state and fluid solutions at room temperature with some of them exhibiting aggregation-induced emission (AIE). These complexes have been applied as photosensitizers in light-induced oxidative functionalization of secondary and tertiary benzylic amines as well as in light-induced hydrogen production, with a maximum of 175 turnovers for hydrogen produced. Palladium(II) complexes containing two types of tetradentate dianionic O DEGREESN DEGREESC DEGREESN ligand systems (Systems 1 and 2) have been prepared and show constrasting photophyical properties. A full scale time-resolved spectroscopic analysis has been done on some of these complexes and a platinum(II) analogue. These complexes are found to have similar excited state decay pathway( 〖S_1〗 DEGREESi→〖S_1〗 DEGREESf→T) with ΦISC of about unity. The emission efficiency of System 2 complexes is superior to that of System 1 complexes, which is ascribed to the suppression of excited state distortion on the basis of the results of DFT calculations. A lower radiative decay rate of System 2 palladium(II) complexes relative to the platinum(II) analogue has been found, which could be due to their lower spin-orbit coupling constant. One of the palladium(II) complexes ha

Book Luminescent Platinum ii   Palladium ii  and Gold iii  Complexes Containing Isocyanide  Alkynyl and N Heterocyclic Carbene Ligands

Download or read book Luminescent Platinum ii Palladium ii and Gold iii Complexes Containing Isocyanide Alkynyl and N Heterocyclic Carbene Ligands written by Faan-Fung 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, "Luminescent Platinum(II), Palladium(II) and Gold(III) Complexes Containing Isocyanide, Alkynyl and N-heterocyclic Carbene Ligands: Synthesis, Photophysical Properties and Material Applications" by Faan-fung, Hung, 孔繁峰, 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: Several cyclometalated Pt(II) isocyanide complexes containing C-deprotonated C DEGREESN DEGREESC ligands (C DEGREESN DEGREESC = 2,6-diphenylpyridine derivatives) were synthesized. These complexes display orange-red emissions with max at 582-619 nm and quantum yields of up to 26% in CH2Cl2 at room temperature. The incorporation of carbazole/fluorene/thiophene unit(s) to C DEGREESN DEGREESC ligands leads to minimized structural distortion of complexes in their excited states and thereby suppresses non-radiative decay pathways. The high thermal stability (Td >300 C) renders these complexes good candidates as phosphorescent dopants in organic light-emitting diodes (OLEDs). Red-emitting OLEDs with CIE coordinates of (0.650.01, 0.350.01) were fabricated by vacuum deposition, showing a maximum external efficiency of 12%. In addition, well-defined nano/microstructures were obtained from self-assembly of these complexes driven by π∙∙∙π, C-H∙∙∙π and C-H∙∙∙H-C interactions as observed in the crystal structures. Two series of organopalladium(II) alkynyl complexes containing a terpy (terpy = 2,2':6',2''-terpyridine) or C DEGREESN DEGREESC pincer carbene ligand (C DEGREESN DEGREESC = 2,6-bis(1-butylimidazol-2-ylidenyl)pyridine) were prepared. These complexes are non-emissive in solution at room temperature except that the one containing both C DEGREESN DEGREESC and pyrenylacetylide ligands shows phosphorescence (Φ = 0.3%) originating from intraligand state of the acetylide ligand. This could be attributed to the strong -donating N-heterocyclic carbene (NHC) in the pincer ligand that strongly destabilizes d-d state, the population of which provides an efficient non-radiative decay channel. To make comparison between Pd(II) and Pt(II) complexes with the two ligand systems, Pt(II) C DEGREESN DEGREESC alkynyl complexes were also prepared. They are emissive in solution and some display excimer emissions at high concentration (〖10〗 DEGREES(-4)-〖10〗 DEGREES(-3) mol 〖10dm〗 DEGREES(-3)). The X-ray crystal structures of [Pd(L)(CCPh)](〖PF〗_6) (L = terpy and C DEGREESN DEGREESC) revealed one-dimensional chain stacking of complex cations with alternating Pd(II)∙∙∙Pd(II) contacts of about 3.29-3.35 A and π-π interactions of about 3.4 A . Well-defined submicron/nanostructures were obtained from self-assembly of Pd(II) and Pt(II) alkynyl complexes driven by π-π interactions between aromatic moieties and/or metal∙∙∙metal interactions. DFT calculations on the optimized structures of [M(L)(CCPh)]+ (M = Pd(II) and Pt(II)) revealed the existence of metal∙∙∙metal closed-shell interactions. In addition, the complex containing the C DEGREESN DEGREESC ligand exhibits slightly enhanced metal∙∙∙metal interactions and larger "bonding" energy upon dimerization. Furthermore, spin-orbit coupling between singlet and triplet excited states is more effective which promotes rapid intersystem crossing. A new class of cyclometalated Au(III) complexes containing C-deprotonated C DEGREESN ligands (C DEGREESN = 2-phenylpyridine and its derivatives) and cis-chelating bis-NHC ligands was synthesized. These are the first examples of Au(III) complexes supported by cis-chelating bis-NHC ligands. They display emissions in solution under degassed condition at room temperature with &

Book Photoluminescent Organoplatinum  II  Complexes Containing N Heterocyclic Carbene  Nhc  Ligands

Download or read book Photoluminescent Organoplatinum II Complexes Containing N Heterocyclic Carbene Nhc Ligands written by Kai Li and published by Open Dissertation Press. This book was released on 2017-01-26 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Photoluminescent Organoplatinum (II) Complexes Containing N-heterocyclic Carbene (NHC) Ligands" by Kai, Li, 李凯, 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: The syntheses, structures, photophysical properties and applications of three types of photoluminescent organoplatinum(II) complexes containing N-heterocyclic carbene (NHC) ligands are described. The tetradentate dianionic bis(phenolate-NHC) type ligands provide a superior scaffold for constructing thermally stable and efficient deep-blue phosphorescent Pt(II) complexes with λmax of 440-460 nm and solid-state emission quantum yields of 30%. Highly efficient blue OLEDs with CIEx, y of (0.19, 0.21) were fabricated based on these emitters with maximum brightness, peak current efficiency and power efficiency of 9500 cd m DEGREES(-2), 24 cd A DEGREES(-1) and 17 lm W DEGREES(-1), respectively. Structural modification by extending the π-conjugation of the tetradentate bis(phenolate-NHC) ligand leads to strongly phosphorescent platinum(II) complexes with long-lived emissive electronic states that can be used as a luminescent sensor for oxygen. DFT/TDDFT calculations and time-resolved spectroscopic characterizations were performed to gain insight into the structure-photophysics correlation. The N-heterocyclic carbene (NHC) ligand was incorporated into Pt(II) complexes containing tridentate deprotonated 1,3-bis(2-pyridyl)benzene (N DEGREESC DEGREESN) type ligand. In addition to the [(N DEGREESC DEGREESN)Pt(NHC)]PF6 type complexes with (N DEGREESC DEGREESN) in η3-tridentate coordination mode, Pt(II) complexes with η2-bidentate (N DEGREESCN) ligands, namely [(N DEGREESCN)Pt(NHC)2]PF6, have been isolated and structurally characterized. The highly phosphorescent [(N DEGREESC DEGREESN)Pt(NHC)]PF6 complexes were used for solution-processed green OLEDs fabrication. The peak current efficiency of 12.5 cd A DEGREES(-1) and maximum brightness higher than 2000 cd m DEGREES(-2) were achieved. The presence of the pendent pyridyl motif causes quenching of emission of the [(N DEGREESCN)Pt(NHC)2]PF6 complexes in solution at room temperature. Turning on solid-state emission of [(N DEGREESCN)Pt(nBu2Im)2]PF6 in the presence of an acidic vapor revealed its potential as a luminescent chemosensor. A class of dicationic platinum(II) terpyridyl complexes containing NHC ligand, namely [Pt(tpy)(NHC)](PF6)2, has been synthesized and structurally characterized. Even in the presence of the strong σ-donating NHC ligand, these complexes are non- or weakly emissive in solution at room temperature. However, this class of complexes displays intense emissions in solid state (298 K and 77 K), in glassy solution (77 K butyronitrile) and in PMMA (2 wt.%, 298 K). The ligand (terpyridine) displacement reaction arising from CN attack onto the Pt(II) center has been observed for [Pt(tpy)(nBu2Im)](PF6)2 leading to its application as a chemodosimeter for selective cyanide sensing in aqueous solution. DOI

Book DESIGN   SYNTHESIS OF LUMINESC

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 Luminescent Palladium II  and Platinum II  Complexes with Tridentate Monoanionic and Tetradentate Dianionic Cyclometallated Ligands

Download or read book Luminescent Palladium II and Platinum II Complexes with Tridentate Monoanionic and Tetradentate Dianionic Cyclometallated Ligands written by Pui-keong Chow and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Luminescent Palladium II  and Platinum II  Complexes with Tridentate Monoanionic and Tetradentate Dianionic Cyclometallated Ligands

Download or read book Luminescent Palladium II and Platinum II Complexes with Tridentate Monoanionic and Tetradentate Dianionic Cyclometallated Ligands written by Pui-keong Chow and published by . This book was released on 2013 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Luminescent Mixed Ligand Square Planar Platinum II  Complexes Containing Dithiolate Or Dithiocarbamate Ligands

Download or read book Luminescent Mixed Ligand Square Planar Platinum II Complexes Containing Dithiolate Or Dithiocarbamate Ligands written by Joanne McDonald Bevilacqua and published by . This book was released on 1994 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book LIGHT EMITTING PLATINUM  II

Download or read book LIGHT EMITTING PLATINUM II written by Wei Lu and published by Open Dissertation Press. This book was released on 2017-01-28 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Light-emitting Platinum (II) and Gold (I) Complexes Containing Cyclometalated and Alkynyl Ligands" by Wei, Lu, 陸為, 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 LIGHT-EMITTING PLATINUM(II) AND GOLD(I) COMPLEXES CONTAINING CYCLOMETALATED AND ALKYNYL LIGANDS Submitted by Lu Wei for the degree of Doctor of Philosophy at The University of Hong Kong in July 2003 The syntheses, characterizations, spectroscopic properties and applications of light-emitting platinum(II) and gold(I) complexes containing cyclometalated and alkynyl ligands are described and five systems are explored in detail. The tuning of the photoluminescent properties of tridentate cyclometalated platinum(II) complexes bearing σ-alkynyl auxiliaries, namely [(C DEGREESN DEGREESN)Pt(C≡C) R] [H(C DEGREESN DEGREESN) = 6-aryl- 2,2'-bipyridine; n = 1-4; R = aryl, alkyl or trimethylsilyl], through modifications of both the cyclometalating and acetylide ligands, is presented. These neutral Pt(II) materials exhibit enhanced stability during vacuum deposition. Organic light-emitting devices (OLEDs) based on these emitters display orange to red electrophosphorescence with low turn-on voltages ( 4 V), maximum luminance -2 -1 approaching 10,000 cd m and efficiencies up to 4.2 cd A . The crystal structures and photoluminescence of tethered trinuclear cyclometalated platinum(II) complexes, 3+ namely [{R(C DEGREESN DEGREESN)} Pt ( -dpmp)] (R denotes substituent(s) on the (C DEGREESN DEGREESN) 3 3 3 ligand, dpmp = bis(diphenylphosphinomethyl)phenylphosphine), were investigated and compared with their mono- and binuclear analogues to yield insight into the nature of their respective excited states. The emission energies were found to be dependent on the substituents on the cyclometalating ligands and the oligophosphine 8 8 ligands, and sensitive to d -d and π-π interactions. Intermolecular π-stacking interactions were found to affect the crystal packing, solid-state emission energy and vapochromic behavior of mono- and multinuclear dicyclometalated Pt(II) complexes, 1 1 namely [Pt(C DEGREESN DEGREESC)L ] [HC DEGREESN DEGREESCH = 2,6-diphenylpyridine; L = pyridine, isocyanide, 2 2 phosphine], [Pt (C DEGREESN DEGREESC) (-L )] [L = pyrazine, bidentate phosphine] and 2 2 [Pt (C DEGREESN DEGREESC) ( -dpmp)], and aromatic α-diimine Pt(II) complexes bearing 3 3 3 t t functionalized σ-alkynyl auxiliaries, namely [( Bu bpy)Pt(C≡CAr) ] ( Bu bpy = 4,4'- 2 2 2 bis-tert-butyl-2,2'-bipyridine, Ar = 4-pyridyl, 3-pyridyl, 2-pyridyl, 4-ethynylpyridyl, 2-thienyl and pentafluorophenyl). The weak non-covalent interactions observed in the solvated crystal structures, such as π-π, C-H---π(C≡C), C-H---N(py), C-H---F-C and Cl---Cl contacts, were invoked to rationalize the reversible VOC (volatile organic compound) sensing and signaling capabilities of these materials. The syntheses, crystal structures and spectroscopic properties of several π-conjugated carbon-rich scaffolds bearing [Au(PCy )] (Cy = cyclohexyl) termini are described. The ν of the 3 0-0 acetylenic (ππ*) emission for [(Cy P)Au(C≡C) Au(PCy )] (n = ∞) was estimated to 3 n 3 -1 1 occur at 11000 cm by extrapolation of the plot of ν versus 1/n. Prompt (ππ*) 0-0 fluorescence only was detected from the cross-conjugated species [TEE][Au(PCy )] 3 4 ([TEE]H = tetraethynylethene). A correlation between the solid-state emissions and crystal structures of the phosphorescent polymorphic complex [4-NO - C H C≡CAu(PCy )] and their related complexes was observed, and a rationale based 6 4 3 on excitonic coupling is proposed. DOI: 10.5353/th_b

Book Luminescent Platinum II  Complexes with Tridentate N donor Ligands as Building Blocks for Supramolecular assembled 1D Materials and Metallofoldamers

Download or read book Luminescent Platinum II Complexes with Tridentate N donor Ligands as Building Blocks for Supramolecular assembled 1D Materials and Metallofoldamers written by 黃進熙 and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Highly Luminescent Platinum Complexes for Light Emitting Devices and Bio Imaging

Download or read book Highly Luminescent Platinum Complexes for Light Emitting Devices and Bio Imaging written by Lisa Murphy and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Intensely luminescent cyclometallated platinum(II) complexes have been prepared containing N C N-coordinating ligands, based on 1,3-dipyridylbenzene. Exceptionally high quantum yields (0.85, degassed DCM, 298 K) are rationalised in terms of the particularly short Pt-C bond, which raises the energy of the normally deactivating d-d* state. Terdentate ligand functionalisation has been employed to obtain complexes with tuneable emission. Fluorination at the 3,5-aryl positions and/or placing electronreleasing substituents at the 4-pyridyl position gave complexes with blue-shifted emission, whilst retaining a high quantum yield. Substitution of the chloride ancillary ligand for cyanide led to further blue-shifts. In general, these complexes undergo intermolecular interactions in solutions of higher concentration to form excimers. The excimers are emissive in their own right, and display broad, structureless emission bands at lower energy than the isolated molecules (monomers). The influence of substituents in the terdentate ligand and the identity of the coligand on the energy and relative intensity of excimer emission has been elucidated. Some complexes have been used as phosphorescent dopants in the fabrication of high efficiency organic light emitting devices (OLED)s. The colour of a device depends on the monomer-to-excimer emission ratio, which is controlled by varying the dopant concentration. At intermediate concentrations, white OLEDs, with properties approaching pure white light, have been obtained. Preliminary investigations into the utility of the complexes as bio-imaging agents in live cells are reported. The complexes which contain small substituents on the terdentate ligand enter cells rapidly, retaining their phosphorescence. These Pt(II) complexes appear to localise simultaneously in both the nucleus and mitochondria of cells, where their emission characteristics differ: the application of appropriate filter sets allows separate visualisation of the two organelles. A selection of iridium(III) complexes were also investigated as bio-imaging agents. These complexes localise in cytoplasm-based organelles, and do not appear to enter the nucleus. Both classes of organometallic complexes are shown to be suitable candidates for time resolved emission imaging microscopy (TREM).

Book Photoluminescent and Electroluminescent Properties of Neutral Platinum  II  Complexes Containing Alkynyl and Multi Anionic Ligands

Download or read book Photoluminescent and Electroluminescent Properties of Neutral Platinum II Complexes Containing Alkynyl and Multi Anionic Ligands written by Siu-Chung Chan and published by . This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Luminescent Platinum ii   Copper i   Silver i  and Zinc ii  Complexes with Functional Pyridyl and Arylacetylide Ligands

Download or read book Luminescent Platinum ii Copper i Silver i and Zinc ii Complexes with Functional Pyridyl and Arylacetylide Ligands written by Yongyue Lin and published by . This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: