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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.
71

Theoretical investigations of polyhedral inorganic molecules

Johnston, Roy Luigi January 1986 (has links)
This Thesis describes some theoretical studies on cluster compounds of the main group and transition metal elements. Chapter 1 presents a review of the theoretical aspects of cluster chemistry. Three major theoretical approaches are identified, namely the localised, delocalised and free electron models and their historical development is described. The research described in this Thesis is based on extensions of Stone's Tensor Surface Harmonic (TSH) methodology, supported by Extended Huckel molecular orbital calculations. In Chapter 2, the TSH approach is used to describe the skeletal bonding in 3- and 4-connected polyhedral clusters. Like the deltahedral clusters, 4-connected molecules are generally characterised by (n+1) Skeletal Electron Pairs (SEP's). 3- connected clusters, however, possess 3n/2 SEP's. This difference is attributed to the occurrence of additional non-bonding orbitals in the 3-connected case. In Chapter 3, the bonding in a novel class of deltahedral metallaborane clusters is discussed. These hyper-closo or iso-closo species are studied from a fragment orbital viewpoint, regarding the structures as metal-capped fragments of a borane icosahedron. In this way, the problem of whether these clusters possess n or (n+1) SEP's is studied for n=9, 10 and 11. Although most deltahedral clusters conform to the (n+1) SEP rule, there are a significant number which do not. In Chapter 4, these deviations are rationalised from a group theoretical/topological viewpoint. A group theoretical paradigm is developed which simplifies the derivation of the frontier orbitals for these molecules. Chapter 5 extends the TSH methodology to clusters with bispherical topologies. To discuss these clusters, the TSH wavefunctions are modified to include radial, as well as angular nodes. The methodology is also applied to clusters with toroidal topologies, where the capping atoms form a ring around the equator of the inner cluster sphere. The bonding in π-donor- and π-acceptor-bridged clusters of the transition metals are compared in Chapter 6. Although the symmetry aspects are identical and lead to similar bonding patterns, the ir-donor clusters are characterised by a number of unoccupied d<sup>δ</sup>-based orbitals. The bonding in a series of closo, nido and arachno π-donor clusters, based on edge- and face-bridged octahedral molecules is considered and a relationship between the cluster electron count and the number of unavailable d<sup>δ</sup>-based orbitals is identified.
72

Magnetism and magnetic excitations in narrow band metals and rare-earth compounds

Bahurmuz, Abdulrahim A. January 1976 (has links)
No description available.
73

D3 Chromophores - geometric distortion in trigonal-dihedral transition metal chromophores and its relevance to optical circular dichroism

Butler, Keith Raymond January 1973 (has links)
2 v. : ill. ; 26 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--Dept. of Physical and Inorganic Chemistry, University of Adelaide, 1974
74

A preparative and kinetic study of selenite substitution with aquo transition metal complexes

Fowless, Alan David January 1973 (has links)
vii, 165 [14] leaves : ill. ; 26 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physical and Inorganic Chemistry, 1973
75

Synthetic, structural and spatial studies of rhenium compounds.

Wei, Yi. Lock, C.J.L. Unknown Date (has links)
Thesis (Ph.D.)--McMaster University (Canada), 1995. / Source: Dissertation Abstracts International, Volume: 56-12, Section: B, page: 6741. Adviser: C. J. L. Lock.
76

D3 Chromophores - geometric distortion in trigonal-dihedral transition metal chromophores and its relevance to optical circular dichroism.

Butler, Keith Raymond. January 1973 (has links) (PDF)
Thesis (Ph.D.) -- Dept. of Physical and Inorganic Chemistry, University of Adelaide, 1974.
77

A preparative and kinetic study of selenite substitution with aquo transition metal complexes.

Fowless, Alan David. January 1973 (has links) (PDF)
Thesis (Ph.D.) -- University of Adelaide, Dept. of Physical and Inorganic Chemistry, 1973.
78

Transition metal complexes of protoporphyrin IX formed by reaction with metals on clays

Klube, John Arthur, January 1976 (has links)
Thesis (M.S.)--South Dakota School of Mines and Technology, Rapid City, 1976. / Vita. Includes abstract. Includes bibliographical references (leaf 29). Also issued in print.
79

Phosphorescent emissions of coinage metal-phosphine complexes theory and photophysics /

Sinha, Pankaj. Omary, Mohammad A., January 2009 (has links)
Thesis (Ph. D.)--University of North Texas, Dec., 2009. / Title from title page display. Includes bibliographical references.
80

Transition metal complexes of protoporphyrin IX formed by reaction with metals on clays

Klube, John Arthur, January 1976 (has links)
Thesis (M.S.)--South Dakota School of Mines and Technology, Rapid City, 1976. / Vita. Includes abstract. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaf 29).

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