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Interactions Of Silver And Gold Complexes With Sulphide Minerals: A Surface Study, Michael John Scaini
Interactions Of Silver And Gold Complexes With Sulphide Minerals: A Surface Study, Michael John Scaini
Digitized Theses
This thesis examines the interactions of the aqueous species {dollar}\rm Ag\sp+,\ AgCl\sb{lcub}x{rcub}\sp{lcub}1-x{rcub},\ AuCl\sb4\sp-{dollar} and AuSH with the surfaces of PbS, (Zn,Fe)S and FeS{dollar}\sb2{dollar} with the aim of better understanding the role that sulphide minerals play in concentrating precious metals from solution. Through the use of surface (XPS, AES, SEM) and conventional (AAS, IC, electrochemistry) analytical techniques, insight into mineral modification, metal chemistry and morphology, alloy composition and solution chemistry is obtained.;Reactions of Ag{dollar}\sp+{dollar} and the three minerals resulted in the presence of Ag{dollar}\sb2{dollar}S and Ag(0) being observed on all mineral surfaces, in a 2 step process where Ag{dollar}\sb2{dollar}S, then Ag(0) …
Variable Energy Photoelectron Spectra Of Organometallic Compounds Of The Late Transition Metals, Xiaorong Li
Variable Energy Photoelectron Spectra Of Organometallic Compounds Of The Late Transition Metals, Xiaorong Li
Digitized Theses
This thesis describes photoelectron spectroscopy (PES) studies with variable photon energy for organometallic molecules of late transition metals, including cobalt, rhodium, iridium, nickel, palladium, platinum, copper, and silver. Synchrotron radiation (in the range of 30 to 170 eV photon energy) and traditional helium I (21.22 eV) and helium II (40.81 eV) light sources were used in this study, with the aid of theoretical ground state and cross section calculations by using X{dollar}\alpha{dollar}-SW and Gelius model methods. With these techniques the variation of band intensities as a function of photon energy were investigated. The very different intensity features between metal d …
Homo- And Hetero-Nuclear Clusters Of Platinum And Rhenium, Leijun Hao
Homo- And Hetero-Nuclear Clusters Of Platinum And Rhenium, Leijun Hao
Digitized Theses
ABSTRACT HAS BEEN ARCHIVED 07/22/97;
Spectroscopic Properties Of Copper Binding To The Protein Metallothionein, Anna Rae Green
Spectroscopic Properties Of Copper Binding To The Protein Metallothionein, Anna Rae Green
Digitized Theses
Metallothionein (MT) is a low molecular weight protein found in the kidneys and livers of all mammals. Twenty of its 61 or 62 amino acid residues are cysteinyl residues, allowing the protein to act as an impressive chelating agent. Although it has been well established that mammalian MT binds seven M(II) (M = Cd(II), Zn(II), Hg(II)) ions tetrahedrally in two metal-thiolate clusters of the form M{dollar}\sb4{dollar}(S{dollar}\rm\sb{lcub}cys{rcub})\sb{lcub}11{rcub},{dollar} (the {dollar}\alpha{dollar} domain) and {dollar}\rm M\sb3(S\sb{lcub}cys{rcub})\sb9,{dollar} (the {dollar}\beta{dollar} domain), little is known about the structure of copper-containing metallothioneins. In this thesis, absorption, circular dichroism (CD) and emission spectroscopies and excited state lifetime data are …
Reactions Of Group 14-Halide Bonds With Dimethylplatinum(Ii) Complexes, Christopher James Levy
Reactions Of Group 14-Halide Bonds With Dimethylplatinum(Ii) Complexes, Christopher James Levy
Digitized Theses
The oxidative addition of E-X bonds (E = Si, Ge, Sn; X = halide) to {dollar}\lbrack\rm PtMe\sb2(diimine)\rbrack{dollar} yields a number of new Pt(IV) complexes containing Pt-E linkages. The complexes {dollar}\lbrack\rm PtXMe\sb2(Me\sb3Si)(diimine)\rbrack{dollar} (X = Br, I) are the first well-characterized examples of Pt(IV)-silyl species. The X-ray structure of {dollar}\lbrack\rm PtIMe\sb2(Me\sb3Si)(bipy)\rbrack{dollar} shows the longest single Pt-I bond reported, and demonstrates the very strong trans influence of the {dollar}\rm Me\sb3Si{dollar} ligand. The X-ray structure of {dollar}\lbrack\rm PtIMe\sb2(Me\sb3Sn)(bipy{dollar}-{dollar}\sp{lcub}t{rcub}\rm bu\sb2)\rbrack{lcub}\cdot{rcub}0.5Me\sb3SnI{lcub}\cdot{rcub}CH\sb2Cl\sb2{dollar} reveals a five coordinate {dollar}\rm Me\sb3SnI{dollar} unit with a novel {dollar}\rm I\cdot\cdot\cdot Sn{dollar}-I interaction.;Many of the Pt-Sn systems studied involve the rapid reversible oxidative addition …
Structural Studies On Silver(I) Metallothionein, Ziqi Gui
Structural Studies On Silver(I) Metallothionein, Ziqi Gui
Digitized Theses
Metallothioneins (MT) are a class of low molecular weight, cysteine rich proteins in almost all living things. These proteins have been found to bind a wide range of metals both in vivo and in vitro due to the unusually high cysteinyl sulfur content. The metallothioneins are believed to possess the ability to store and transport essential metals, such as Zn(II) and Cu(I), and also to detoxify toxic metals, such as Cd(II) and Hg(II). However, the precise physiological functions of these proteins still remain unclear to date. As silver(I)-metallothioneins have shown different stoichiometric ratios of Ag:MT from Zn(II)- and Cd(II)-metallothioneins in …
Circular Dichroism And Luminescence Studies Of Copper Binding To Metallothionein, Paul Anthony Presta
Circular Dichroism And Luminescence Studies Of Copper Binding To Metallothionein, Paul Anthony Presta
Digitized Theses
The metallothioneins (MT) are a class of low molecular weight, cysteine rich proteins found in almost all living things. The high sulfhydryl content imparts to these proteins the unique ability to bind a wide range of metals. The metallothioneins have been implicated in the storage and transport of essential metals, such as zinc and copper, and in the detoxification of toxic metals, such as cadmium. However, the exact physiological functions of these proteins remain a matter of speculation. In particular, little is known about the interactions of copper with MT. In this thesis, the structural and mechanistic properties of copper …
Magnetic Circular Dichroism Spectroscopy Of Phthalocyanine Anions, John Douglas Mack
Magnetic Circular Dichroism Spectroscopy Of Phthalocyanine Anions, John Douglas Mack
Digitized Theses
An upgraded version of the program SIMPFIT is used to carry out deconvolution analyses on the uv-visible absorption and magnetic circular dichroism (MCD) spectra of zinc phthalocyanine, ZnPc({dollar}-{dollar}2), and the ring reduced anion radical of zinc phthalocyanine, (ZnPc({dollar}{lcub}-3{rcub})\rbrack\sp-.{dollar} A detailed study of the temperature dependence of the absorption and MCD spectra of ZnPc({dollar}-{dollar}2) shows that a significant fraction of the spectral intensity observed at room temperature can be assigned as 'hot' bands. This results in a significant discrepancy in the absorption and MCD band widths of the major transitions. Spectral band deconvolution was therefore carried out on data recorded at …
Adamantane-Like Clusters Of The Zinc-Group Elements, Yuyang Wu
Adamantane-Like Clusters Of The Zinc-Group Elements, Yuyang Wu
Digitized Theses
Three new types of chalcogenate-bridged adamantane-like clusters of the zinc-group elements have been studied in detail: those with alkylthiolates as bridging ligands, formulated as (({dollar}\mu{dollar}-{dollar}\rm SAlk)\sb6(MX)\sb4\rbrack\sp{lcub}2-{rcub}{dollar} (Alk = Me, Et, 1-Pr, 2-Pr, 1-Bu, 2-Bu, c-{dollar}\rm C\sb6H\sb{lcub}11{rcub}{dollar}(Cy), or CH{dollar}\sb2{dollar}Ph (Bz); M = Zn, Cd, or Hg; X = Cl, Br, or I); those with phosphines as terminal ligands, formulated as (({dollar}\mu{dollar}-ER){dollar}\sb6{dollar}(CdPPh{dollar}\sb3)\sb{lcub}4-n{rcub}{dollar}(Cd){dollar}\sb{lcub}n{rcub}\rbrack \sp{lcub}2+{rcub}{dollar} (E = S or Se; R = 1-Pr, 2-Pr, 1-{dollar}\rm C\sb5H\sb{lcub}11{rcub}{dollar} (1-Pe), Cy, or Ph; n = 0, 1, or 2); and those with halides as bridging ligands, formulated as (({dollar}\mu{dollar}-ER){dollar}\sb{lcub}6-m{rcub}(\mu{dollar}-X){dollar}\sb{lcub}m{rcub}{dollar}(MX){dollar}\sb4\rbrack\sp{lcub}2-{rcub}{dollar} (E = S or Se; R = Et, …
Aluminum, Silicon, Phosphorus And Sulfur K- And L-Edge X-Ray Absorption Spectroscopy Of Minerals And Glasses: Applications In Mineralogy And Geochemistry, Dien Li
Digitized Theses
Al, Si, P and S K- and L-edge X-ray absorption near-edge structure (XANES) spectra of a large selection of metal sulfide and silicate minerals and some glasses have been studied using monochromatized synchrotron radiation.;S K- and L-edge XANES spectra of metal sulfides are qualitatively interpreted based on MO/energy band models, reveal the DOS of unoccupied S s-, p- and d-like states, provide new insight into the electronic structure of the conduction band, and demonstrate the bonding interaction of metal d electrons with S 3s and 3p electrons. The S K- and L-edges shift to high energy with increase in oxidation …
Oxidative Addition As A New Route To Organometallic Polymers And Dendrimers, Sudhir Achar
Oxidative Addition As A New Route To Organometallic Polymers And Dendrimers, Sudhir Achar
Digitized Theses
This thesis describes new routes to organometallic polymers and dendrimers employing an oxidative addition method. The new complexes {dollar}\lbrack\rm PtMe\sb2(NN)\rbrack{dollar} 1, (1b: (NN) = 4,4{dollar}\sp\prime{dollar}-di-tert-butyl-2,2{dollar}\sp\prime{dollar}-bipyridine; 1c: (NN) = 4,4{dollar}\sp\prime{dollar}-dimethyl-2,2{dollar}\sp\prime{dollar}-bipyridine; 1d: (NN) = 4-vinyl-4{dollar}\sp\prime{dollar}-methyl-2,2{dollar}\sp\prime{dollar}-bipyridine) were shown to be useful precursors to polymers. {dollar}\{lcub}{dollar}Note 1a: (NN)= 2,2{dollar}\sp\prime{dollar}-bipyridine{dollar}\{rcub}{dollar}.;The oxidative addition of organic halides (R-X) to 1 gave {dollar}\lbrack\rm PtXMe\sb2R(NN)\rbrack{dollar} {dollar}\rm\{lcub} (NN)\sb{lcub}1a{rcub}{dollar}: R-X = methyl 2-(bromomethyl)acrylate; 2-(bromomethyl)acrylic acid; 2-bromoethyl methacrylate; methyl bromoacetate; ethyl bromoacetate; bromoacetic acid; bromoacetonitrile and bromoacetamide. {dollar}\rm (NN)\sb{lcub}1b{rcub}{dollar}: (R-X) = 2-bromoethyl methacrylate and vinyl bromoacetate. {dollar}\rm (NN)\sb{lcub}1d{rcub}{dollar}: vinyl bromoacetate; 2-bromoethyl methacrylate; acryloyl chloride and vinylbenzyl chloride{dollar}\{rcub}{dollar}.;The free radical polymerization of the …
Ionic Conductivity Of Rubidium Chloride, Marcia Lee Vernon
Ionic Conductivity Of Rubidium Chloride, Marcia Lee Vernon
Digitized Theses
This investigation describes a theoretical and experimental examination of the defect properties of rubidium chloride. A theoretical study of the defect properties of RbBr and RbI is also presented.;Defect energy calculations were carried out on RbCl, RbBr and RbI using the HADES code and electron-gas potentials that were fitted to the crystal properties. Damping of the long-range dispersion energy was introduced during fitting of the potential and in the calculation of perfect lattice and defect properties.;In addition, defect energy calculations were done on Rb{dollar}\sb2{dollar}S using potentials developed for the RbCl:S{dollar}\sp{lcub}2-{rcub}{dollar} system. These calculations represent the first theoretical study of the …
Transition Metal Rimmed Calixarenes And Their Supramolecular Chemistry, Wei Xu
Transition Metal Rimmed Calixarenes And Their Supramolecular Chemistry, Wei Xu
Digitized Theses
This thesis describes the design and the synthesis of novel anion and cation receptors in which sets of transition metal atoms are introduced on the rims of calixarene bowls.;A bowl-shaped calixresorcinarene 1 has been derivatized to incorporate either four phosphonite units to give a phosphonito-cavitand 2 or eight phosphinite units to give a phosphinito-calixresorcinarene 3. These derivatives have been used as multidentate ligands to incorporate transition metals on the upper-rim of the calixresorcinarene bowl. The chlorogold(I) complex of 4, 2(AuCl){dollar}\sb4{dollar} which was characterized by an X-ray structure determination, is shown to contain three AuCl units around the upper rim of …
Chemistry Of Binuclear And Cluster Complexes Of Ruthenium, Cobalt And Nickel, Hameed A. Mirza
Chemistry Of Binuclear And Cluster Complexes Of Ruthenium, Cobalt And Nickel, Hameed A. Mirza
Digitized Theses
The work described in this thesis is mainly focused on the synthesis, characterization and chemical reactivity of dinuclear and trinuclear phosphine substituted carbonyl complexes of Ru, Co and Ni. The thesis can be broadly classified into three sections. The first section comprising chapters 2 and 3, deals with the chemistry of dinuclear and trinuclear ruthenium complexes with dppm, bis(diphenylphosphino)methane, bridging ligands. The reaction mixture RuCl{dollar}\sb3{dollar}/dppm/NaBH{dollar}\sb4{dollar}/CO yielded mainly trans- (RuCl{dollar}\sb2{dollar}(dppm){dollar}\sb2{dollar}). However, when silver acetate was added to the reaction mixture prior to the reduction with NaBH{dollar}\sb4{dollar}, a high yield synthesis of (Ru{dollar}\sb2{dollar}({dollar}\mu{dollar}-CO)(CO){dollar}\sb4{dollar}({dollar}\mu{dollar}-dppm){dollar}\sb2{dollar}) was achieved. In addition, (RuH(CO)(dppm){dollar}\sb2{dollar}) {dollar}\sp+{dollar} and the electron …
High-Resolution Photoelectron Spectroscopy Using Synchrotron Radiation: Ligand Field And Vibrational Splitting And Chemical Effects On Linewidths, Jeffrey N. Cutler
High-Resolution Photoelectron Spectroscopy Using Synchrotron Radiation: Ligand Field And Vibrational Splitting And Chemical Effects On Linewidths, Jeffrey N. Cutler
Digitized Theses
High resolution photoelectron spectra of numerous Group IV, VII and VIII compounds have been recorded using a newly constructed photoelectron spectrometer based on the McPherson ESCA 36 hemispherical analyzer. This spectrometer is designed to make use of the high electron resolution and transmission of the analyzer coupled with the tunability and high photon resolution which is inherent in synchrotron radiation.;For the first time using this instrument, it has become possible to differentiate between three distinct core level broadening mechanisms: vibrational and ligand field splitting and a chemical effect on linewidths. Several I 4d photoelectron spectra of seven different iodine-containing compounds …
Metal And Ring Oxidation In Metallophthalocyanines, Edward A. Ough
Metal And Ring Oxidation In Metallophthalocyanines, Edward A. Ough
Digitized Theses
Absorption and magnetic circular dichroism (MCD) spectra of neutral and oxidized magnesium and iron phthalocyanine (MgPc and FePc) are reported. Chemical, electrochemical and photochemical methods are employed in the generation of the stable {dollar}\pi{dollar}-cation radical of magnesium phthalocyanine. The broad absorption band at 500 nm is a "marker" band that verifies oxidation of the phthalocyanine ring. Variable temperature absorption and EPR spectra indicate that oxidized MgPc({dollar}-{dollar}1) exists in solution as a mixture of monomer ( (MgPc({dollar}-{dollar}1)) {dollar}\cdot\sp+{dollar})and dimer ( (MgPc({dollar}-{dollar}1)) {dollar}\sbsp{lcub}2{rcub}{lcub}++{rcub}{dollar}). Least squares and Simplex calculations were performed on the absorption and MCD spectra of MgPc({dollar}-{dollar}2) and MgPc({dollar}-{dollar}1) to determine …
Studies Of The Interactions Of Oxygen And Water With Aluminum(100), Stephen James Bushby
Studies Of The Interactions Of Oxygen And Water With Aluminum(100), Stephen James Bushby
Digitized Theses
The interactions of O{dollar}\sb2{dollar} and water with Al(100) have been studied by Nuclear Reaction Analysis (NRA), Thermal Desorption Spectroscopy (TDS), measurement of the work function ({dollar}\Delta\phi{dollar}), Photoelectron Spectroscopy (PES) and Fourier Transform InfraRed-Reflection Absorption Spectroscopy (FTIR-RAS). The major findings of this study are: The {dollar}\sp{lcub}18{rcub}{dollar}O(p,{dollar}\alpha)\sp{lcub}15{rcub}{dollar}N nuclear reaction is a useful alternative for determining absolute oxygen coverages by NRA. The absolute coverage of oxygen on Ni(100) at 300 K as a function of {dollar}\sp{lcub}18{rcub}{dollar}O{dollar}\sb2{dollar} exposure has been measured; the coverage of 2.45 {dollar}\pm{dollar} 0.10 ML (1 monolayer (ML) on Ni(100) = 1.61 {dollar}\times{dollar} 10{dollar}\sp{lcub}15{rcub}{dollar} particles cm{dollar}\sp{lcub}-2{rcub}{dollar}) at saturation corresponds to 3-3.4 …
Thermal Diffusion In Electrolyte Solutions, Hui Lu
Thermal Diffusion In Electrolyte Solutions, Hui Lu
Digitized Theses
1. A conductimetric technique has been used to study the thermal diffusion of dilute aqueous solutions of Me{dollar}\sb4{dollar}NBr, Me{dollar}\sb4{dollar}NIi, Et{dollar}\sb4{dollar}NBr, Et{dollar}\sb4{dollar}NI, Pr{dollar}\sb4{dollar}NBr, Pr{dollar}\sb4{dollar}NI, Pr{dollar}\sb4{dollar}NOH, Bu{dollar}\sb4{dollar}NCl, Bu{dollar}\sb4{dollar}NBr, Bu{dollar}\sb4{dollar}NI, Bu{dollar}\sb4{dollar}NSCN, Bu{dollar}\sb4{dollar}PCl, NaPh{dollar}\sb4{dollar}B, Ph{dollar}\sb4{dollar}PCl and Ph{dollar}\sb4{dollar}AsCl (Me = methyl, Et ethyl, Pr = propyl, Bu = butyl, Ph = phenyl). The enthalpies of transport of these salts, {dollar}H\sp*{dollar}, have unusual concentration dependences. For Me{dollar}\sb4{dollar}NBr and Me{dollar}\sb4{dollar}NI, {dollar}H\sp*{dollar} is almost constant. For the tetrabutylammonium salts, {dollar}H\sp*{dollar} passes through minima at high dilutions. {dollar}H\sp*{dollar} increases with concentration for the rest of salts. Only for Pr{dollar}\sb4{dollar}NOH does {dollar}H\sp*{dollar} decrease with concentration, which is the normal concentration …
Interactions Of Oxygen With Zirconium(0001), Bernard Jerome Flinn
Interactions Of Oxygen With Zirconium(0001), Bernard Jerome Flinn
Digitized Theses
Interactions of oxygen with Zr(0001) have been studied using low energy electron diffraction (LEED), work function ({dollar}\Delta\phi{dollar}), static and dynamic secondary ion mass spectrometry (SSIMS, DSIMS), thermal desorption spectroscopy (TDS), Auger electron spectroscopy (AES) and nuclear reaction analysis (NRA).;The initial sticking coefficient of oxygen is close to unity up to {dollar}\sim{dollar}0.75 ML at 90, 293 and 473 K. Oxygen chemisorption is disordered at room temperature and below, with some oxygen locating in on-top sites and some subsurface. Heating the disordered surface to {dollar}\sim{dollar}473 K causes all oxygen to move to subsurface sites and a (1 x 2) ordered oxygen underlayer …
Gas Phase And Surface Reactions In Organometallic Chemical Vapour Deposition Of Platinum, Eric Chuan-Whatt Ou
Gas Phase And Surface Reactions In Organometallic Chemical Vapour Deposition Of Platinum, Eric Chuan-Whatt Ou
Digitized Theses
Organometallic chemical vapour deposition (OMCVD) films usually have carbon as an impurity. This comes from the decomposition of the ligands in the organometallic precursor. Understanding the chemical reactions in the decomposition will greatly enhance our ability to control the impurity level in these films and also the epitaxial growth of the films. Depending on the pressure in the reactor, the important reactions could be in the gas phase or on the surface.;Decomposition of the precursor, cis-dimethyl platinum diisocyanide in presence of hydrogen shows reduction in carbon impurity. The decomposition was carried out in an infrared gas cell so that infrared …
Homo- And Hetero-Dinuclear Complexes Of Cobalt, David J. Elliot
Homo- And Hetero-Dinuclear Complexes Of Cobalt, David J. Elliot
Digitized Theses
The work presented in this thesis concerns the synthesis and characterization of a series of novel phosphine-carbonyl complexes of cobalt. Chapters 2 and 3 outline mononuclear and homodinuclear cobalt complexes, chapters 4 and 5 discuss heterobimetallic complexes (CoM(CO){dollar}\sb{lcub}\rm n{rcub}{dollar}({dollar}\mu{dollar}-dppm){dollar}\sb2{dollar}) (M = Rh,n = 3; M = Mn or Re, n = 5), and finally chapters 6 and 7 discuss complexes containing the {dollar}\mu{dollar}-PPh{dollar}\sb2{dollar} group and the complex ((CO){dollar}\sb2{dollar}({dollar}\eta\sp1{dollar}-dppm) Co({dollar}\mu{dollar}-dppm)BH{dollar}\sb2{dollar}), respectively.;Introduction of CO into Co(II)/phosphine/NaBH{dollar}\sb4{dollar} reaction systems, previously shown to produce a number of interesting complexes, has provided a novel approach to the synthesis of phosphine-carbonyl complexes of cobalt. A number …
Homo- And Heteronuclear Clusters Of Platinum And Gold, Ravindranath Ramachandran
Homo- And Heteronuclear Clusters Of Platinum And Gold, Ravindranath Ramachandran
Digitized Theses
This thesis documents the chemistry of some homo- and heteronuclear cluster complexes of gold and platinum.;The reaction of (AuC{dollar}\equiv{dollar}C{dollar}t{dollar}-Bu) with the diphosphine ligands, CH{dollar}\sb2{dollar}(PR{dollar}\sb2{dollar}){dollar}\sb2{dollar} (R = Me, dmpm; R = Ph, dppm; R = {dollar}-{dollar}OMe, dmopm), yielded a number of complexes. Complexes ({dollar}t{dollar}-BuC{dollar}\equiv{dollar}C-Au-R{dollar}\sb2{dollar}PCH{dollar}\sb2{dollar}OR{dollar}\sb2{dollar}) (R = Me, Ph) were fluxional in solution. The crystal structures of (Au{dollar}\sb2{dollar}({dollar}\mu{dollar}-dmpm){dollar}\sb2{dollar}) X{dollar}\sb2\cdot{dollar}2H{dollar}\sb2{dollar}O (X = C{dollar}\ell{dollar}, I) were determined, as was that of (Au{dollar}\sb2{dollar}(C{dollar}\equiv{dollar}C{dollar}t{dollar}-Bu){dollar}\sb2{dollar}({dollar}\mu{dollar}-dppm)). Complex (CH{dollar}\sb2\{lcub}{dollar}P(MeO){dollar}\sb2{dollar}Au(C{dollar}\equiv{dollar}C{dollar}t{dollar}-Bu){dollar}\{rcub}\sb2{dollar}) oligomerized in chlorinated solvents to give (Au{dollar}\sb2{dollar}(C{dollar}\equiv{dollar}C{dollar}t{dollar}-Bu){dollar}\{lcub}\mu\sb3- {dollar}(MeO){dollar}\sb2{dollar}PCHP(OMe){dollar}\sb2\{rcub}{dollar}) {dollar}\sb3{dollar}, and then (Au{dollar}\sb8{dollar}C{dollar}\ell\sb2\{lcub}\mu\sb3- {dollar}(MeO){dollar}\sb2{dollar}PCHP(OMe){dollar}\sb2\{rcub}\sb2\{lcub}\mu\sb4- {dollar}(MeO){dollar}\sb2{dollar}PCP(OMe){dollar}\sb2\{rcub}\sb2{dollar}) {dollar}\cdot{dollar}CHC{dollar}\ell\sb3{dollar}. The structure of the octagold cage was determined by X-ray crystallography, and was shown to …
Gas Phase Photoelectron Studies Of Organoplatinum Complexes Using Helium I, Helium Ii And Synchrotron Radiation, Dong-Sheng Yang
Gas Phase Photoelectron Studies Of Organoplatinum Complexes Using Helium I, Helium Ii And Synchrotron Radiation, Dong-Sheng Yang
Digitized Theses
Gas-phase He I and He II photoelectron spectra of four series of organoplatinum complexes are reported, together with synchrotron radiation photoelectron spectra of CpPtMe{dollar}\sb3{dollar} (Cp = {dollar}\eta\sp5{dollar}-C{dollar}\sb5{dollar}H{dollar}\sb5{dollar}) and PtMe{dollar}\sb2{dollar} (COD) (COD = 1,5-cyclooctadiene). The platinum complexes investigated with both He I and He II sources include square-planar cis-dimethylplatinum(II), square-planar cis-bis(trifluoromethyl)platinum(II), half-sandwich ({dollar}\eta\sp5{dollar}-cyclopentadienyl)trimethylplatinum(IV), and octahedral-like ({dollar}\beta{dollar}-diketonato)trimethylplatinum(IV) complexes. The electronic structures of the complexes studied are discussed using the He I and He II spectral information, such as the ionization energy shifts from ligand substitutions and the resolved vibrational splittings from ligand-based orbitals, and using X{dollar}\alpha{dollar}-SW calculations on some model compounds. The …
Stereoelectronic Effects, Mechanism, And Synthesis In Sulfonyl Chemistry, Rajendra Rathore
Stereoelectronic Effects, Mechanism, And Synthesis In Sulfonyl Chemistry, Rajendra Rathore
Digitized Theses
ABSTRACT HAS BEEN ARCHIVED 09/17/93;
X-Ray Photoelectron Spectroscopic Studies Of The Interaction Of Aqueous Metal Complexes With Sulphide Minerals, Margaret Mary Hyland
X-Ray Photoelectron Spectroscopic Studies Of The Interaction Of Aqueous Metal Complexes With Sulphide Minerals, Margaret Mary Hyland
Digitized Theses
This thesis examines the interaction of aqueous metal complexes, KAuCl{dollar}\sb4{dollar}, Na{dollar}\rm\sb3Au(S\sb2O\sb3)\sb2{dollar}, Na{dollar}\rm\sb2PdCl\sb4{dollar} and HgCl{dollar}\sb2{dollar}, with the surfaces of the sulphide minerals, FeS{dollar}\sb2{dollar}, PbS and (Zn,Fe)S. The aim of this work was to gain a better understanding of the role of sulphide minerals in controlling metal concentrations in ore depositing and other natural aqueous systems. Scanning electron microscopy (SEM) and the surface sensitive techniques of Auger electron spectroscopy, and in particular, X-ray photoelectron spectroscopy, provided information relating to the chemical and morphological changes occurring at the mineral surface. Atomic absorption spectroscopy was used to monitor solution concentrations.;KAuCl{dollar}\sb4{dollar} is reduced to Au(0) …
The Coordination Chemistry Of Hexafluoroacetone Hydrate, Rosemary Catherine Hynes
The Coordination Chemistry Of Hexafluoroacetone Hydrate, Rosemary Catherine Hynes
Digitized Theses
This thesis discusses the coordination chemistry of the fluorinated gem-diol, (CF{dollar}\sb3)\sb2{dollar}C(OH){dollar}\sb2{dollar}, "hexafluoroacetone hydrate" (HFAH). Due to the electron-withdrawing ability of the CF{dollar}\sb3{dollar} groups, the protons of this diol are acidic. Reactions of the diol with metal chlorides and alkali metal hydroxides were found to give fluorinated alkoxide complexes in which HFAH adopted four distinct coordination modes. The nature of the metal, and the amount and steric requirements of the coligand, if any, used, were identified as major factors in determining which coordination mode was adopted. The four observed modes are (i) as a chelating dialkoxide, {dollar}\rm\sp-OC(CF\sb3)\sb2O\sp-{dollar}, (ii) as a dimerized, …
Reactivity Of A Triplatinum Cluster, Michael Craig Jennings
Reactivity Of A Triplatinum Cluster, Michael Craig Jennings
Digitized Theses
This thesis examines the reactivity of the coordinatively unsaturated triplatinum cluster (Pt{dollar}\sb3(\mu\sb3{dollar}-CO)({dollar}\mu{dollar}-dppm){dollar}\sb3{dollar}) (PF{dollar}\sb6{dollar}) {dollar}\sb2{dollar}. This complex can act as a model for a triangle of Pt atoms on a Pt(111) surface and this thesis describes studies of its reactivity towards various main group reagents.;Hydrogen sulphide yielded the cation (Pt{dollar}\sb3{dollar}(H)({dollar}\mu\sb3{dollar}-S) ({dollar}\mu{dollar}-dppm){dollar}\sb3{dollar}) {dollar}\sp+{dollar}, which was characterized crystallographically. In addition, the reaction of H{dollar}\sb2{dollar}S with the analogous palladium species (Pd{dollar}\sb3{dollar}({dollar}\mu\sb3{dollar}-CO)({dollar}\mu{dollar}-dppm){dollar}\sb3{dollar}) (PF{dollar}\sb6{dollar}) {dollar}\sb2{dollar} was also examined. Isolobal substitution of the hydride of the platinum sulphido cluster with a triphenylphosphino gold cation yielded (Pt{dollar}\sb3{dollar}(AuPPh{dollar}\sb3{dollar})({dollar}\mu\sb3{dollar}-S)({dollar}\mu\sb3{dollar}-AgCl) ({dollar}\mu{dollar}-dppm){dollar}\sb3{dollar}) (PF{dollar}\sb6{dollar}) which incorporated a neutral AgCl ligand into the cluster …
Coordination Chemistry Of A Coordinatively Unsaturated Trinuclear Platinum Cluster, Arleen Marie Bradford
Coordination Chemistry Of A Coordinatively Unsaturated Trinuclear Platinum Cluster, Arleen Marie Bradford
Digitized Theses
This thesis examines the reactivity of the coordinatively unsaturated triplatinum cluster (Pt{dollar}\sb3(\mu\sb3{dollar}-CO){dollar}(\mu{dollar}-dppm){dollar}\sb3\rbrack{dollar} (PF{dollar}\sb6\rbrack \sb2{dollar}, 1. The complex can act as a model for a triangle of platinum atoms on a Pt(111) surface and this thesis describes studies of its reactivity towards various main group reagents.;The halide ions, Cl{dollar}\sp-{dollar}, Br{dollar}\sp-{dollar} and I{dollar}\sp-{dollar}, yielded the clusters (Pt{dollar}\rm\sb3(\mu\sb3{dollar}-CO){dollar}(\mu\sb3{dollar}-X)({dollar}\mu{dollar}-dppm){dollar}\sb3\rbrack \sp{lcub}1+{rcub}{dollar} which were characterized spectroscopically. Attempts were made to investigate the bonding in these systems with respect to the degree of ionic, or covalent, character in the Pt{dollar}\rm\sb3(\mu\sb3{dollar}-X) bonds through ligand exchange studies.;Monodentate tertiary phosphines and phosphites yielded the clusters (Pt{dollar}\rm\sb3(\mu{dollar}-CO)L{dollar}(\mu{dollar}-dppm){dollar}\sb3\rbrack\sp{lcub}2+{rcub}{dollar}, L = phosphine or …
Ligand Effects In Binuclear And Trinuclear Platinum Diphosphine Complexes, Ian Ronald Jobe
Ligand Effects In Binuclear And Trinuclear Platinum Diphosphine Complexes, Ian Ronald Jobe
Digitized Theses
This is a study into the steric and electronic factors governing the synthesis and reactivity of some platinum diphosphine complexes. We report the preparation of a number of new diphosphine ligands: The ethyl and methyl derivatives of (RO){dollar}\sb2{dollar}PCH{dollar}\sb2{dollar}P(OR){dollar}\sb2{dollar} and (Me{dollar}\sb{lcub}\rm n{rcub}{dollar}C{dollar}\sb5{dollar}H{dollar}\sb{lcub}\rm 5-n{rcub})\sb2{dollar}PCH{dollar}\sb2{dollar}P(C{dollar}\sb6{dollar}H{dollar}\sb{lcub}\rm 5-n{rcub}{dollar}Me{dollar}\sb{lcub}\rm n{rcub})\sb2{dollar}, where n = 1 ({dollar}p, m{dollar} and {dollar}o{dollar}-tolyl), 2 ({dollar}m{dollar}-xylyl) and 3 (mesityl).;The preparation and characterization of some platinum(II) complexes, (PtX{dollar}\sb2{dollar}(R{dollar}\sb2{dollar}PCH{dollar}\sb2{dollar}PR{dollar}\sb2)\rbrack\sb{lcub}\rm n{rcub}{dollar}, where X = halide or methyl, have shown how the bulk of the ligand, R{dollar}\sb2{dollar}PCH{dollar}\sb2{dollar}PR{dollar}\sb2{dollar}, can have dramatic effects upon the nuclearity, n, and upon the conformations adopted by the Pt{dollar}\sb2{dollar}P{dollar}\sb4{dollar}C{dollar}\sb2{dollar} rings in binuclear …
A Photoelectron Study Of The Bonding Ability Of Phosphine And Isocyanide Ligands In Organometallic Complexes, Lisa Marie Dignard
A Photoelectron Study Of The Bonding Ability Of Phosphine And Isocyanide Ligands In Organometallic Complexes, Lisa Marie Dignard
Digitized Theses
High resolution ultraviolet photoelectron spectra of substituted tungsten carbonyl derivatives have been measured. The study of the photoelectron peaks due to the tungsten 5d orbitals in the series of complexes (W(CO){dollar}{lcub}\rm\sb{lcub}n{rcub}L\sb{lcub}6-n{rcub}{rcub}{dollar}) has demonstrated that the Ligand Additivity Model holds for the systems where L are tertiary phosphine ligands. This work confirms that the splitting of the tungsten 5d orbitals observed in the photoelectron spectra can be described in terms of ligand field effects and are not dominated by relaxation effects.;The substituent effects of methyl and phenyl groups in isocyanide and tertiary phosphine ligands have been studied by photoelectron, infrared and …