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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Luminescent cyclometalated gold (III) complexes with ancillary N-heterocyclic carbene and alkynyl ligands : from design, synthesis, photophysics to supramolecular assembly and functions

Au, Ka-man, 區嘉雯 January 2012 (has links)
A library of luminescent cyclometalated gold(III) complexes containing various bis-cyclometalating R-C^N^C ligands derived from 2,6-diphenylpyridine and ancillary alkynyl ligands, [Au(R-C^N^C)(C≡CR’)], has been synthesized. Some of the complexes have been structurally determined by X-ray crystallography. These complexes were found to exhibit intense emission in dichloromethane solution at 298 K, originating from metal-perturbed triplet intraligand (IL) excited states of the R-C^N^C ligand, with substantial charge transfer character from the aryl moiety to the pyridyl ring. In the presence of electron-rich alkynyl ligands, the emission origin could be switched to an alkynyl-to-cyclometalating ligand ligand-to-ligand charge transfer (LLCT) excited state. This class of complexes was also demonstrated to show rich electroluminescence properties as emitters in organic light-emitting devices. In addition, the supramolecular assembly of this class of complexes has also been revealed in gelation studies. N-Heterocyclic carbenes have been incorporated into the gold(III) metal center to prepare a series of luminescent mononuclear and dinuclear gold(III) complexes, [{Au(C^N^C)}n(NHC)](PF6)n and [{Au(tBuC^N^CtBu)}n(NHC)]- (PF6)n (n = 1, 2). The X-ray crystal structures of most of the complexes have been determined. The emissions of these complexes were assigned to originate from the metal-perturbed intraligand excited state of the bis-cyclometalating ligand. One of the C2-bridged dinuclear complexes was found to exhibit two distinct reduction couples, tentatively correlated to the presence of significant intramolecular π-π interaction in the complex. Two novel series of luminescent mononuclear alkynylgold(III) complexes, [Au(C^N)(C≡CR)2] (HC^N = 2-phenylpyridine (Hppy) and derivatives) and [Au(C^N^N)(C≡CR)]PF6 (HC^N^N = 6-phenyl-2,2’-bipyridine and derivatives), have been synthesized. Some of the X-ray crystal structures have been determined. The former class of complexes with bidentate C^N ligands has been observed to show tunable emission spanning across the visible spectrum from 462 to 697 nm. With the exception of [Au(ppy)(C≡C-C6H4-NH2-p)2] which showed a low-energy band originated from a 3LLCT [π(C≡C-C6H4-NH2)→π*(C^N)] excited state, all complexes exhibited vibronic-structured emission bands originated from the intraligand transition of the cyclometalating C^N ligand in dichloromethane solution at 298 K. On the other hand, most of the complexes with the tridentate C^N^N-type ligand have been observed to exhibit vibronic-structured emission bands attributed to the intraligand transition of the C^N^N ligand in low-temperature butyronitrile glass. / published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
82

Addition reactions of some substituted indoles with dimethyl acetylenedicarboxylate and methyl propiolate

蔡志強, Choi, Chi-keung, Michael. January 1983 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
83

Disposition and hepatotoxicity of 1,2-dibromoethane

Plescia, Frank Harry January 1981 (has links)
No description available.
84

Mass spectrometric studies and cryogenic reactivity of CF[subscript]2 and CI[subscript]2

Martin, William Joseph 05 1900 (has links)
No description available.
85

Heats of mixing for liquid systems containing chloride, hydroxyl and methylene groups : measurement and prediction by an analytical group solution model

Kalu, Egwuonwu Ukoha. January 1975 (has links)
No description available.
86

Metabolic impairment of the posterior cingulate cortex and reversal by methylene blue a novel model and treatment of early stage Alzheimer's disease /

Riha, Penny Denise, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.
87

Rate constants and mechanisms for reactions of carbenes and cations from oxadiazolines and other precursors /

Pezacki, John Paul. January 1998 (has links)
Thesis (Ph.D.) -- McMaster University, 1999. / Includes bibliographical references (leaves 260-271). Also available via World Wide Web.
88

N-heterocyclic carbenes with pendant arylamine donor substituents as supports for metal-metal interactions of closed shell metal ions

Moore, Adam L. January 2008 (has links)
Thesis (Ph. D.)--University of Nevada, Reno, 2008. / "December, 2008." Includes bibliographical references. Online version available on the World Wide Web.
89

Rhodium-mediated carbene insertion synthesis of (-)-hamigeran B and the (-)-sordaricin core /

Tian, Weiwei. January 2008 (has links)
Thesis (Ph.D.)--University of Delaware, 2008. / Principal faculty advisor: Douglass F. Taber, Dept. of Chemistry & Biochemistry. Includes bibliographical references.
90

Reactivity of bis(amino)cyclopropenylidenes (BACs) and cyclic (alkyl)(amino)carbenes (CAACs) coordination chemistry, catalysis, and small molecule activation /

Kuchenbeiser, Glenn Richard. January 2009 (has links)
Thesis (Ph. D.)--University of California, Riverside, 2009. / Includes abstract. Available via ProQuest Digital Dissertations. Title from first page of PDF file (viewed March 10, 2010). Includes bibliographical references. Also issued in print.

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