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This thesis describes the synthetic, structural and reactivity studies of η- cycloheptatrienyl-molybdenum and -tungsten chemistry. Chapter 1 presents an overview of the chemistry of η-cycloheptatrienyl derivatives of transition metals, in particular group 6 metals. The functional group properties of the η-cycloheptatrienyl ligand are also discussed. Chapter 2 describes the synthesis of [Mo(η-C₇H₇)(η⁵-C₇H₉)] from Mocl₅ or [MoCl₄(thf)₂], which provides a convenient route to η-cycloheptatrienyl-molybdenum compounds, such as [Mo(η-C₇H₇)LX₂] and [Mo(η-C₇H₇)L₂X], where L = tertiary phosphines or acetonitrile and X = halogen, [NBu₄] [Mo(η-C₇H₇)I₃], [Mo(η-C₇H₇)(η- C₅H₄R)] (R = H or Me) and [Mo(η-C₇H₇)(η⁵-C₉H₇)]. The X-ray crystal structures of [Mo(η-C₇H₇)(MeCN)I₂], [NBu₄][Mo(η-C₇H₇))I₃] and [Mo(η-C₇H₇)(η-C₅H₄Me)] are presented. The compound [Mo(η-C₇H₇))(MeCN)I₂], mixed with Me₃SiCH₂MgCl, is a catalyst for ring-opening polymerisation of norbornene giving trans polymer exclusively. The electron-transfer complexes [Mo(η-C₇H₇)(η-C₅H₄Me)][tcne] and {[Mo(η-C₇H₇))(η- C₅H₅}₂[tcnq]} and the intercalation compound {ZrS₂[Mo(η-C₇H₇)(η-C₅H₄Me)]o.22} are also described. An extension of these synthetic pathways to tungsten is described in chapter 3. Reduction of WCl₆ with sodium amalgam in the presence of cycloheptatriene gives [W(η- C₇H₇)(η⁵-C₇H₉)], which is a precursor to the compounds [W(η-C₇H₇)(MeCN)I₂], [W(η- C₇H₇)(PMe₃)X₂] (X = Br or I), [W(η-C₇H₇)(dmpe)I], [W(η-C₇H₇)(η-C₅H₄R)] (R = H or Me) and [Mo(η-C₇H₇)(η⁵-C₉H₇)]. The [W(η-C₇H₇)(MeCN)I₂] / Me₃SiCH₂MgCI system is an active catalyst for ring opening polymerisation of norbomene. The electronic structures of [W(η-C₇H₇)(η-C₅H₄R)] (R= H or Me) are discussed on the basis of their He I and He II photoelectron spectra. The intercalation of [W(η-C₇H₇)(η-C₅H₄Me)] into ZrS<suv>2</sub> is also described. The magnetic properties of the 17-electron compounds [Mo(η-C₇H₇)(MeCN)I₂], [Mo(η-C₇H₇)(PMe₃)I₂], [W(η-C₇H₇)(MeCN)I₂], [W(η-C₇H₇)(PMe₃)I₂] and [W(η-C₇H₇) (PMe₃)I₂] are discussed in chapter 4. They behave as one-dimensional antiferromagnets which was suggested by magnetic model fittings and the crystal structure of [Mo(η-C₇H₇)(MeCN)I₂]. Chapter 5 comprises of two parts. The first part describes a new series of binuclear thiolato-bridged molybdenum complexes [(η-C₇H₃R¹₄)Mo(μ-SR²)₃ Mo- (η-C₇H₃R¹₄)][BF₄] (R¹ = H or Me; R² = Et, Pr, Bu, Ph or CH₂Ph). Dynamic NMR studies reveal that all of these complexes (except for R² = Ph) are fluxional due to inversion at the pyramidal sulfur centre. Cyclic voltammetric studies show that they undergo two reversible one-electron reductions. Second part of this chapter describes the new bridging-imido compound [(η-C₇H₇)Mo(μ-NAr)₂Mo(η-C₇H₇)] (Ar = 2,6- diisopropylphenyl). Chapter 6 discusses the η-l,2,4,6-tetramethylcycloheptatrienyl-molybdenum system. The new η-tetramethylcycloheptatriene molybdenum compounds [M'(η-C₇H₄Me₄- 1,3,5,7)],[M'(η-C₇H₄Me₄-l,2,4,6)] and [M'(η-C₇H₄Me₄-l,3,4,6)], M' = Mo(CO)₃, and new η-tetramethylcycloheptatrienyl-molybdenum compounds [M"(CO)₃]+, [M"(CO)₂C1], [M"(dmpe)Cl], [M"(η-C₆H₅Me)]+ and [M"(acac)(PPh₃)], M" = Mo(η- CC₇H₃Me₄-1,2,4,6), and [Mo(η³-C₇H₃Me₄-l,2,4,6)(dmpe)(CO)₂Cl] are described. Chapter 7 gives the experimental details for the work described in preceeding chapters. Appendix A presents characterising data for all the new compounds and previously unreported data for known compounds. Crystallographic details for the X-ray structure determinations and X-ray powder diffraction data are listed in Appendix B and C respectively.

This thesis is divided into two parts. The first part concerns the synthesis and characterisation of substituted metallocene complexes of the transition and main group metals. The second part describes the preparation and characterisation of inorganic fullerene (IF)-related materials. <strong>Chapter 1</strong> reviews the chemistry of dialkyl- and diaryl-phosphino substituted cyclopentadienyl complexes of the transition metals. <strong>Chapter 2</strong> describes the synthesis and characterisation of the new ligands [M(C₅Me₄)CH₂PMe₂] (M = H, Li, Na and K) via the precursors [HC₅Me₄)CH₂PHMe₂][X] (X = Cl and PF₆). The synthesis, characterisation and chemical reactivity of the compounds [Zr{{η-C₅Me₄)CH₂PMe₂}₂Cl₂ and [Mn{η-C₅Me₄)CH₂PMe₂}₂] is reported together with supporting evidence for the synthesis of the bimetallic complex [Zr{U+03B7-C₅Me₄)CH₂PMe₂}₂Cl₂PtI₂] and the complex [Mn{η-C₅Me₄)CH₂PMe₂B(C₆F₅)₃}₂]. <strong>Chapter 3</strong> provides a brief introduction into the field of main group metallocenes and describes the synthesis and characterisation of the new main group metallocenes [M{η- C₅H₄)CMe₂PMe₂}₂] (M = Pb and Sn). The B(C₆F₅)<sub>3 adduct [Pb{η-C₅H₄)CMe₂PMe₂(B(C₆F₅)₃}₂] has also been synthesised. The main group - transition metal bimetallic complex [Pb{η-C₅H₄)CMe₂PMe₂}₂PtI<sub>2<sub> in which the substitutedplumbocene acts as a bidentate ligand, has been characterised by mass spectrometry and ³¹P{¹H}NMR spectroscopy. <strong>Chapter 4</strong> provides an introduction into the field of IF-related materials and an overview of the analytical techniques used in their characterisation. <strong>Chapter 5</strong> describes the preparation and characterisation of IF-MoS₂ and IF-(Nb,W)S₂ materials from MoC and the binary oxides Nb₈ W₉O₄₇ and Nb₄W₁₃O₄₇ respectively. A powder X-ray diffraction study of the conversion of WC to WO_3-X and the subsequent sulfidisation by H₂S to form novel IF-WS₂ morphologies is also described. <strong>Chapter 6</strong> describes the preparation of amorphous Group 5 metal (V, Nb and Ta) oxides using the metal vapour synthesis technique. These amorphous precursors have been annealed in a reducing atmosphere to form the oxide phases U+03B1-V₂O₃, NbO₂ and TT-Ta₂O₅ which have been identified by powder X-ray diffraction. Upon reaction with H₂S, the crystalline oxides afford layered sulfides of the form MS₂ (M = V, Nb and Ta), some of which exhibit behaviour typical of IF-like materials and have been characterised by HRTEM, powder X-ray diffraction and EDX analysis. Chapter 7 outlines the experimental details for the synthesis, characterisation, reactions and compounds described in the preceding chapters. <strong>Chapter 8</strong> presents the characterising data for the new compounds described in chapters 2 and 3. <strong>Appendix A</strong> contains details of the crystallographic data for the structurally characterised compound [Mn{η-C₅Me₄)CH<sub>PMe₂}₂].

Electrochemical capacitors (ECs) have drawn much attention owing to their fast charging/discharging rate, and long lifetime up to millions of cycles. Applications of EC range from large scale transportation to miniaturized electronics. The research reported herein explores the development of an economical process for the synthesis of high performance electrode material for high power ECs. A two stage synthesis process which consists of electroplating of molybdenum oxide followed by thermal nitridation was developed. X-ray diffraction and X-ray photoelectron spectroscopy revealed the material to be Mo oxide with nitrogen substitution, Moz(O,N). In a three electrode system, the Moz(O,N) electrodes showed capacitance as high as 16 mF/cm2. Symmetric EC cells achieved state of the art time constant of 100 ms. Ultrahigh power ECs were demonstrated for the first time using Moδ(O,N) electrodes and SiWA-H3PO4-PVA electrolyte, achieving with 10 ms time constant one of the lowest time constants reported for EC.

Electrochemical capacitors (ECs) have drawn much attention owing to their fast charging/discharging rate, and long lifetime up to millions of cycles. Applications of EC range from large scale transportation to miniaturized electronics. The research reported herein explores the development of an economical process for the synthesis of high performance electrode material for high power ECs. A two stage synthesis process which consists of electroplating of molybdenum oxide followed by thermal nitridation was developed. X-ray diffraction and X-ray photoelectron spectroscopy revealed the material to be Mo oxide with nitrogen substitution, Moz(O,N). In a three electrode system, the Moz(O,N) electrodes showed capacitance as high as 16 mF/cm2. Symmetric EC cells achieved state of the art time constant of 100 ms. Ultrahigh power ECs were demonstrated for the first time using Moδ(O,N) electrodes and SiWA-H3PO4-PVA electrolyte, achieving with 10 ms time constant one of the lowest time constants reported for EC.

Fischer-Tropsch Synthesis (FTS) is known as the most practical way to convert natural gas to hydrocarbon products including synthetic fuel depending on the catalysts and operating conditions. Australia has 25% of world's natural gas resources hence Australia's crude oil dependency can be reduced extensively by developing catalysts that will facilitate the technique of converting natural gas to synthetic fuel. Molybdenum nitride has been employed in this study for FTS because of its superior mechanical strength, stability, exceptional resistance to carbon deposition & suifur poisoning. In particular, molybdenum nitride is endowed with similar electronic properties to those of noble metals. Other transition metal nitrides such as Co nitride and Co-Mo nitride were also investigated in this study. The physicochemical attributes of nitride catalysts were examined by BET surface area, particle dispersion, acid site strength & concentration, and surface elemental composition. Gas to solid nitridation kinetic was thermogravimetrically monitored. CO hydrogenation activity was measured in a fixed bed reactor using various syngas compositions and temperatures at atmospheric pressure. The effect of nitridation conditions on catalytic properties of nitrides was investigated via 23 factorial design. It has revealed that nitridation parameters; temperature, nitriding gas composition (H2:NH3) and nitridation reaction time were all significantly influencing catalyst properties. The optimal nitridation condition was 973 K, H2:NH3=1: 1, and 4 hours of nitriding time which gave higher alkene selectivity. 20 wt% M02N/Ah03 was found to be the better FT catalyst compare to catalysts with lower Mo loading and other inorganic oxide supports. Nitridation kinetic studied by thermogravimetric analysis showed that successful nitridation of transition metal oxide precursor was dependent of nitridation temperature and hydrogen concentration. Co-Mo nitride has several forms of nitride species, COS.47N, C03M03N, MoN, and Mo2N. It was shown that COS.47N was the most active component favouring the CO hydrogenation rate and alkene selectivity. Mechanistically-based kinetic models suggested that methanation over Co nitride occurs mainly via surface carbon while surface oxygenated intermediates were accountable for methanation over Co-Mo nitride and Mo nitride.

Thesis (Ph. D.)--Ohio State University, 2008. / Title from first page of PDF file. Includes bibliographical references (p. 113-119).

Thesis (M.S.)--The University of North Carolina at Greensboro, 2008. / Directed by Bruce Banks; submitted to the Dept. of Chemistry. Title from PDF t.p. (viewed Jul. 31, 2009). Includes bibliographical references (p. 95-102).

Thesis (doctoral)--Technische Universiteit Delft, 1998. / Includes bibliographical references.