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This Thesis is concerned with the synthesis of post-metallocene group 4 amidinate complexes as pre-catalysts for the polymerisation and oligomerisation of α-olefins. Activation of half-sandwich group 4 amidinate complexes with 1,3-conjugated dienes is also investigated and their underlying chemistry is explored. <strong>Chapter 1</strong> introduces homogeneous Ziegler-Natta catalysis, with a specific focus on group 4 compounds. A review of metallocene and post-metallocene complexes of group 4 will also be presented and their behaviour in olefin polymerisation will be discussed. <strong>Chapter 2</strong> describes the synthesis and characterisation of _K1-amidinate supported titanium complexes. Base-free activation of the titanium cyclopentadienyl-amidinate dialkyl complexes will be investigated and the resulting cationic species will be further explored with commonly applied trapping agents. The synthesis and characterisation of new titanium cyclopentadienyl-amidinate diene complexes and their corresponding tri(pentafluorophenyl)borane-activated zwitterionic compounds will also be described and their performance in the co-polymerisation of ethylene and propylene will be discussed. <strong>Chapter 3</strong> explores the addition of 1,3-conjugated diene reagents to titanium cyclopentadienyl-amidinate and guanidinate alkyl cations. Mechanistic and computational studies of allyl and diene formation will also be described. The polymerisation capabilities of the newly formed complex will be discussed and compared to previously reported dialkyl complexes. <strong>Chapter 4</strong> describes the synthesis and characterisation of aminopyridinato titanium complexes and _K1-_K2-bis(amidinate) titanium complexes. The activation chemistry of the newly formed dialkyl complexes will be investigated. Furthermore, the synthesis of a new bis(aminopyridinato) titanium complex will also be discussed alongside their activity in EPM and EPDM polymerisation. <strong>Chapter 5</strong> describes the performance of the aminopyridinato titanium complexes (synthesised in Chapter 4) in EPDM polymerisation. The sensitivity of the aforementioned complexes towards hindered phenols will also be discussed and their behaviour in ethylene oligomerisation will be explored. <strong>Chapter 6</strong> presents full experimental procedures and characterising data for the new complexes reported in this Thesis.

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Organic and organometallic electronic materials continue to attract considerable attention among researchers due to their cost effectiveness, high flexibility, low temperature processing conditions and the continuous emergence of new semiconducting materials with tailored electronic properties. In addition, organic semiconductors can be used in a variety of important technological devices such as solar cells, field-effect transistors (FETs), flash memory, radio frequency identification (RFID) tags, light emitting diodes (LEDs), etc. However, organic materials have thus far not achieved the reliability and carrier mobility obtainable with inorganic silicon-based devices. Hence, there is a need for finding alternative electronic materials other than organic semiconductors to overcome the problems of inferior stability and performance. In this dissertation, I research the development of new transition metal based electronic materials which due to the presence of metal-metal, metal-?, and ?-? interactions may give rise to superior electronic and chemical properties versus their organic counterparts. Specifically, I performed computational modeling studies on platinum based charge transfer complexes and d10 cyclo-[M(?-L)]3 trimers (M = Ag, Au and L = monoanionic bidentate bridging (C/N~C/N) ligand). The research done is aimed to guide experimental chemists to make rational choices of metals, ligands, substituents in synthesizing novel organometallic electronic materials. Furthermore, the calculations presented here propose novel ways to tune the geometric, electronic, spectroscopic, and conduction properties in semiconducting materials. In addition to novel material development, electronic device performance can be improved by making a judicious choice of device components. I have studied the interfaces of a p-type metal-organic semiconductor viz cyclo-[Au(µ-Pz)]3 trimer with metal electrodes at atomic and surface levels. This work was aimed to guide the device engineers to choose the appropriate metal electrodes considering the chemical interactions at the interface. Additionally, the calculations performed on the interfaces provided valuable insight into binding energies, charge redistribution, change in the energy levels, dipole formation, etc., which are important parameters to consider while fabricating an electronic device. The research described in this dissertation highlights the application of unique computational modeling methods at different levels of theory to guide the experimental chemists and device engineers toward a rational design of transition metal based electronic devices with low cost and high performance.

Ho, Ming Gong. / "October 2009." / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 72-75). / Abstracts in English and Chinese. / Table of Contents --- p.V / Acknowledgements --- p.i / Abstract --- p.ii / 摘要 --- p.iv / List of Compounds Synthesized --- p.X / Abbreviation --- p.xi / Chapter Chapter 1 --- Synthesis and Characterization of (9-Anthryl)(iminophosphorano)methanide Group 14 Metal Complexes / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.1.1 --- A General Review of Phosphoranoimine Ligands --- p.1 / Chapter 1.1.2 --- A General Review of Group 14 Metal Complexes Containing Phosphoranoimine Ligands --- p.8 / Chapter 1.2 --- Objectives --- p.9 / Chapter 1.3 --- Results and Discussion --- p.10 / Chapter 1.3.1.1 --- Synthesis of (9-Anthryl)(iminophosphorano)methanide Germanium(II) Chloride [Ge{CH(Pri2P=NSiMe3)(Anth)}Cl] (44) and (9-Anthryl)(iminophosphorano)methanide Tin(II) Chloride [Sn{CH(Pri2P=NSiMe3)(Anth)}Cl] (45) --- p.10 / Chapter 1.3.1.2 --- Spectroscopic Properties of 44 and 45 --- p.11 / Chapter 1.3.1.3 --- Molecular Structures of [Ge {CH(Pri2P=NSiMe3)(Anth)} Cl] (44) and [Sn{CH(Pri2P=NSiMe3)(Anth)} Cl] (45) --- p.11 / Chapter 1.3.2.1 --- Synthesis of Homoleptic Dialkylstannylene [Sn{CH(Pr/2P=NSiMe3)(Anth)}2] (46) --- p.16 / Chapter 1.3.2.2 --- Spectroscopic Properties of 46 --- p.17 / Chapter 1.3.2.3 --- Molecular Structure of [Sn{CH(Pri2P=NSiMe3)(Anth)}2] (46) --- p.17 / Chapter 1.4 --- Experimental Section --- p.20 / Chapter 1.5 --- References for Chapter 1 --- p.23 / Chapter Chapter 2 --- "Synthesis, Characterization and Catalytic Study of (9-Anthryl)(iminophosphorano)methanide Group 4 Metal Complexes" / Chapter 2.1 --- Introduction --- p.27 / Chapter 2.1.1 --- A General Review of Group 4 Metallocene Catalysts in Olefin Polymerization --- p.27 / Chapter 2.1.2 --- A General Review of Group 4 Metal Complexes --- p.28 / Chapter 2.2 --- Results and Discussion --- p.31 / Chapter 2.2.1.1 --- Synthesis of (9-Anthryl)(iminophosphorano)methanide Zirconium(IV) Chloride [Zr{CH(Pri2P=NSiMe3)(Anth)} 2CI2] (57) and (9-Anthryl)(iminophosphorano)methanide Hafnium(IV) Chloride [Hf{CH(Pri2P=NSiMe3)(Anth)}2Cl2] (58) --- p.31 / Chapter 2.2.1.2 --- Spectroscopic Properties of 57 and 58 --- p.32 / Chapter 2.2.1.3 --- Molecular Structures of [Zr{CH(Pri2P^NsiMe3)(Anth)}2CI2] (57) and [Hf{CH(Pri2P=NsiMe3)(Anth)}2Cl2] (58) --- p.32 / Chapter 2.3 --- Catalytic Study of Compounds 57 and 58 on Ethylene Polymerization --- p.37 / Chapter 2.4 --- Experimental Section --- p.39 / Chapter 2.5 --- Reference for Chapter 2 --- p.41 / Chapter Chapter 3 --- "Synthesis, Characterization and Catalytic Study of (9-Anthryl)(thiophosphinoyl)methanide Metal Complexes" / Chapter 3.1 --- Introduction --- p.45 / Chapter 3.2 --- A General Review of Phosphoranosulfide Ligands --- p.45 / Chapter 3.3 --- Objectives --- p.54 / Chapter 3.4 --- Results and Discussion --- p.55 / Chapter 3.4.1.1 --- Synthesis of (9-Anthryl)(thiophosphinoyl)methane [CH2(Pri2P=S)(Anth)] (92) and Lithium Compound [Li(THF)2{CH(Pr/2P=S)(Anth)}] (93) --- p.55 / Chapter 3.4.1.2 --- Spectroscopic Properties of 92 and 93 --- p.56 / Chapter 3.4.1.3 --- Molecular Structures of [Li(THF)2{CH(Pri2P=S)(Anth)}] (93) --- p.57 / Chapter 3.4.2.1 --- Synthesis of Germylgermylene [Ge(GeCl){CH(Pri2P=S)(Anth)}2C12C6H5CH3] (94) --- p.59 / Chapter 3.4.2.2 --- Spectroscopic Properties of 94 --- p.61 / Chapter 3.4.2.3 --- Molecular Structure of [Ge(GeCl){CH(Pri2P=S)(Anth)}2Cl2C6H5CH3] (94) --- p.61 / Chapter 3.4.3.1 --- Synthesis of (9-Anthryl)(thiophosphinoyl)methanide Zirconium(IV) Complex [Zr{CH(Pri2P=S)(Anth)}2Cl2(THF) THF] (95) --- p.64 / Chapter 3.4.3.2 --- Spectroscopic Properties of 95 --- p.64 / Chapter 3.4.3.3 --- Molecular Structure of [Zr{CH(Pri2P=S)(Anth)}2Cl2(THF) THF] (95) --- p.65 / Chapter 3.4.3.4 --- Catalytic Study of [Zr{CH(Pri2P=S)(Anth)}2Cl2(THF) THF] (95)i --- p.68 / Chapter 3.5 --- Experimental Section --- p.69 / Chapter 3.6 --- References for Chapter 3 --- p.72

Cobalt-substituted carboxypeptidase and carbonic anhydrase were chosen as candidates for resonance Raman spectroscopy because they possess visible absorption due to the Co(II)-protein complex. However, no evidence for resonance-enhanced peaks due to the cobalt-containing chromophore was found with laser excitation near the visible absorption bands (514.5 nm) or closer to the ultraviolet absorption bands (457.9nm). Arsanilazocarboxypeptidase and model azotyrosine compounds were selected for a Raman spectroscopic investigation because they have intense absorption bands in the visible region. All of these substances yielded similar resonance Raman spectra. Although there was no evidence for specific zinc-ligand vibrations, shifts in vibrational frequencies of the azotyrosine chromophore could be used as proof of zinc complexation. The protonated azotyrosine model compound was found to have the phenoxy group hydrogen bonded to the azo group, forming a six-membered ring. Replacement of the proton by zinc resulted in the zinc atom being bound only to the phenoxy group. In arsanilazocarboxypeptidase the azotyrosine at position 248 in the polypeptide chain was found to have a structure similar to the protonated model compound, a six-membered ring with zinc bridging the phenoxy group and the azo group. This gave further proof that Tyr 248 is close to the zinc atom in the native enzyme, even in the absence of substrate.

This thesis continues the study into the synthesis and analysis of metal poly - yndiyl complexes. These molecules have shown promise as model molecular wires. The study provides a general overview of the interest in carbon based molecules and introduces the need for molecular electronics. Some of the most promising classes of molecular wires are described before outlining the methods of evaluation. / Thesis (Ph.D.)--School of Chemistry and Physics, 2006.

Thesis (Ph. D.)--University of Oregon, 2007. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 178-191). Also available for download via the World Wide Web; free to University of Oregon users.

M.S. / Chemistry / Resonance Raman spectra of the complex of FeIII-ethylenediamine-tetraacetate with hydrogen peroxide have been obtained in the region of the peroxidic O-O stretching vibration that occurs at 815 cm [superscript -1] in frozen solution. When the complex was prepared from nearly neat, mixed-isotope hydrogen peroxide, H216O18O, a single O-O vibration was observed at 794 cm [superscript -1]. This observation establishes that the two oxygen atoms of the bound peroxide are equivalent and that the peroxide is ligated in an η2 side-on configuration in this mononuclear complex. The absence of any shift in υ(O-O) when the complex was prepared in D2O solvent provides further support for the Fe-OO geometry and rules out the alternative η1 end-on Fe-OOH configuration. In contrast, υ(O-O) of free hydrogen peroxide in the frozen state occurs at 877 cm [superscript -1] in H2Oand at 879 cm [superscript -1] in D2O. The 2- cm [superscript -1] upshift in D2O is similar to that observed previously with oxyhemerythrin and appears to be characteristic of a hydrogen-bonded or protonated peroxide species.

Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 179-189).