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Multi-component determinations using sequential injection analysisTaljaard, Rosa Elizabeth 04 December 2006 (has links)
Please read the abstract in the section 00front of this document / Thesis (PhD (Chemistry))--University of Pretoria, 2006. / Chemistry / unrestricted
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Nuwe aspekte van a-olefien hidroformilering met groep 9 metaalkomplekseJulius, Gerrit Richard 12 1900 (has links)
Thesis (MSc )--Stellenbosch University, 2002. / ENGLISH ABSTRACT:
Please refer to fulltext for abstract / AFRIKAANSE OPSOMMING:
Sien volteks vir opsomming
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Gold(I) and Gold(II) phosphine complexes exhibiting weak AuI... AuI interactions and unsupported AuII-AuII bonds: syntheses, spectroscopy, host-guest chemistry and reactivity studiesLi, Chi-kwan, 李志君 January 2002 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
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Syntheses, structural studies and photophysical properties of mono, diand polynuclear d10-metal complexes with bulky and electron-richphosphine ligands謝文忠, Tse, Man-chung. January 1999 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
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Group 4 complexes bearing tridentate aryloxide-based ancillaryligands: synthesis, characterization andapplication as olefin polymerization catalystsTam, Ka-ho., 譚家豪. January 2006 (has links)
published_or_final_version / abstract / Chemistry / Doctoral / Doctor of Philosophy
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Proteomic and biochemical studies of cytotoxic gold(I), silver(I) and rhodium(II) complexesYan, Kun, 嚴琨 January 2007 (has links)
published_or_final_version / abstract / Chemistry / Doctoral / Doctor of Philosophy
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Metal-metal interactions in homo- and hetero-metallic complexes containing d0, d8 and d10 metal ions: spectroscopic and theoretical studiesXia, Baohui., 夏寶輝. January 2002 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
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Spectral intensities in planar copper(II) complexesEssex, Sarah Jane January 1992 (has links)
No description available.
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Comparative X-ray Structure Analyses of Multidentate Transition Metal ComplexesFlood, Kelly-Jayne January 2006 (has links)
The biological significance of macrocyclic complexes has been recognized since they were first synthesized by Neil Curtis. They have the potential to play a critical role in mimicking metalloprotein active sites. Nine Curtis macrocyclic complexes have been studied using X-ray crystallographic techniques. Their structures have been solved and comparisons of the results have been made. Biological importance is also true of the macrocyclic counterpart; side-off and end-off compartmental ligands. In some circumstances these types of ligands are more appropriate because they have extra flexibility due to their pendant arms not being fixed in place by another head-unit, like a traditional macrocycle. The synthesis of a proposed compartmental ligand; 2,2-(N,Nʼ-bis(benzimidazole-2-ylmethyl)methylamine-5,5ʼ-di-tert-butyl-3,3ʼmethanediyl-dibenzyl alcohol (Ligand 1(L1)), has been proposed and outlined. The pendant arms: bis(benzimidazole-2-ylmethyl)amine (BBIM), were successfully synthesized and characterized with 1H NMR, IR and X-ray crystallography. The head-unit: 5,5ʼ-Di-tert-butyl-2,2ʼ-dihydroxy-3,3ʼ-methanediyl-dibenzene methanol (DHTMBA), of L1 was synthesized and characterized using 1H NMR, IR and mass spectrometry. A similar head-unit; 5,5ʼ-Di-methyl-2,2ʼ-dihydroxy-3,3ʼ-methanediyl-dibenzene methanol (DHMMBA), was synthesized in an effort to shorten the synthetic time of the head-unit. This was consequently converted to the chlorine analogue; 3,3ʼ-Bis(chloromethyl)-5,5ʼ-dimethyl-2,2ʼ-methane-diyldiphenol (Cl-DHMMB), and characterized with 1H NMR, IR and X-ray crystallography. Efforts were made to synthesize Ligand 1, but due to synthetic difficulties and time restraints this proved unsuccessful. Suggestions have been made to develop this synthesis.
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Ionization-structure relationships in metal-phosphine interactions.Jatcko, Mark Edward January 1989 (has links)
The techniques of valence photoelectron spectroscopy (PES), X-ray diffraction, molecular orbital calculations, and multi-nuclear NMR are combined in a comparison of metal-phosphine bonding in a series of phosphine substituted molybdenum and tungsten metal carbonyl complexes, M(CO)(6-n)(P)(n) [n = 1,2,3,4,6]. The phosphine, P, represents either the mono-dentate phosphine, PMe₃, or one phosphine unit in the diphosphines, Me₂P(CH₂)ₓPMe₂, [x = 1, bis(dimethylphosphino)methane (DMPM); x = 2, 1,2-bis(dimethylphosphino)ethane (DMPE)]. Comparison of PMe₃ and the diphosphines in mono-dentate coordination (i.e. η¹-Mo(CO)₅DMPE) indicates the σ-donor strength is essentially identical for the three phosphines studied. Comparison of PMe₃ and the diphosphines in cis-chelating geometries reveals essentially identical charge at the coordinated phosphorus atoms and nearly identical charge at the metal center for cis-M(CO)₄(PMe₃)₂ and cis-M(CO)₄DMPE despite different local P-M-P bond angles. The X-ray crystal structures reveal a "twist" of the phosphine ligand when in sterically strained coordination geometries. The phosphine twist results in a "bent" metal-phosphine bond and is evaluated based on both electronic and steric considerations. The phosphine twist principle is used in studies on the nature of phosphine ligand electronic effects in the M(CO)(6-n)(P)(n) series at high substitution numbers, n. The PES data of the DMPE complexes for n = 4, cis-Mo(CO)₂(DMPE)₂, and n = 6, Mo(DMPE)₃, show symmetric metal electronic structure, but also a deviation from the previously observed additive behavior of phosphine electronic effects. The PES data for cis-Mo(CO)₂(PMe₃)₄ reveal a symmetric metal electronic structure due to sterically induced ligand-ligand interactions in this metal carbonyl complex. Multi-nuclear NMR data (³¹P and ⁹⁵Mo) are presented and the results discussed in light of the important ligand-ligand interactions observed in the PES studies. In addition, comparison of the NMR results for the mono-dentate and chelating phosphine complexes and the PES metal electronic structures provides a possible contribution to the ring chelate effect that is observed in the ³¹P and ⁹⁵Mo chemical shifts. The ring chelate effect refers to the unexplained relative differences between the ³¹P and ⁹⁵Mo chemical shifts of the cis-(PR₃)₂ complexes and the chelating diphosphine analogues.
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