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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.
241

Structural studies of some mononuclear and polynuclear metal complexes

Coxall, Robert Andrew January 1999 (has links)
No description available.
242

The Eco RV restriction endonuclease : an investigation using resonance raman spectroscopy and oligonucleotide phosphorothioates

Thorogood, Harry January 1996 (has links)
No description available.
243

Structural studies of complexes of some S-block elements

Horsburgh, Lynne January 1996 (has links)
No description available.
244

Scale dependence in the properties of galaxy clusters

Lloyd-Davies, Edward Justin January 2001 (has links)
No description available.
245

Crystallographic studies of the sequence selective interactions of ligands within the minor groove of AT-rich DNA

Simpson, Ian John January 1999 (has links)
No description available.
246

Novel thiophene based macrocycles

Sloman, Zachary Scott January 1999 (has links)
No description available.
247

Models of x-ray emission from clusters of galaxies

Pallister, I. C. January 1987 (has links)
No description available.
248

Neutron reflection from interfaces

Li, Zhi Xin January 1996 (has links)
No description available.
249

Optical observations of the supersoft sources

Southwell, Karen Anne January 1997 (has links)
No description available.
250

Synthesis, structure and reaction studies of diphosphine rhodium complexes

Crabtree, Simon Peter January 1996 (has links)
A series of complexes of the type [Rh(diphos)(C(_7)H(_8))](BF(_4)) (1) have been synthesised and two of these species [diphos = Bu(^1)(_2)P(CH(_2))(_2)PBu(^1)(_2), Cy(_2)P(l,2-trans-cyclopentane)PCy(_2)] have been characterised by X-ray crystallography. The influence of the chelating diphosphine on the structural characteristics and NMR parameters of these compounds has been investigated. Complexes of the type (1) are active catalysts for the hydroformylation of l-hexene(120ºC, 450psi 2:1 H(_2):C0). However, they are inactive for the related hydroesterification process and this is attributed to the stability of [Rh(diphos)(CO)(_2)]^ under the reaction conditions. Detailed studies of the reactions of type (1) complexes with H(_2) have been undertaken. The products from these reactions are dependent on both the diphosphine and the solvent employed. In THF and CD(_2)Cl(_2), dimeric hydrides were observed, whilst in CDCl(_3) hydrido-chloro-complexes of the type [Rh(_z)(diphos)(_2)(|µCl)H(_2)](^2+) were formed. In the former solvents, three types of hydrides have been identified by NMR studies, namely [Rh(_2)(diphos)(_2)H(_6)], [Rh(_2)(diphos)(_2)H(_4)] and [Rh(_2)(diphos)(_2)H(_4)](^2+). The oxidative-addition reactions of alkyl-, acyl- and formyl-halide with Rh(I) complexes have been investigated. The reaction with ClCO(_2)Me with [Rh(dppe)Cl](_2) and [Rh(dppe)](_2)(BF(_4))(_2) led to the formation of diphosphine-rhodium(III)-halide species (H(_3)NOH)[Rh(dppe)Cl(_4)] and [Rh(_2)(dppe)(_2)(µ-Cl)(_3)Cl(_2)](BF(_4)) respectively. Alternative routes to these complexes have been investigated starting from RhCl(_3).3H(_2)O/diphosphines and a series of the novel halide bridged dimers have been characterised, including by X-ray crystallography and their reaction chemistry explored. In the synthesis of the cationic rhodium complexes from neutral chloro-complexes with AgBF(_4), the novel silver complexes [Ag(_2)(µ-Bu(^t)(_2)P(CH(_2))(_3)PBu(^t)(_2))(_2)](BF(_4))(_2), [{Ag(H(_2)O)}(_2)(µ-Bu(^t)(_2)P(CH(_2))(_2)PBu(^t)(_2))](BF(_4))(_2), and [Ag(C(_6)D(_6))(_3)BF(_4)] have been isolated as by-products and characterised by X-ray crystallography.

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