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