In this study, we focus on the substituent effect of the diketone ligands on the structural variation of £]- diketonato metal complexes containing N,N-dimethyl formamide (DMF). Three £]-diketones (hfac, bztf, bzbz) were used, and six-, five-, four- coordinated complexes were found accordingly. It is surprising to find that all six metal-oxygen bonds in the M(hfac)2(DMF)2 complexes are of equal length, seemly in violation of Jahn-Teller theorem. Possible reasons for this observation were discussed in this thesis.

Der Wärmeübergang an gestapelte Güter spielt eine wesentliche Rolle bei der ökonomischen Auslegung von Thermoprozessanlagen. Gleichungen für die Wärmeübertragung an solch komplexe Geometrien sind aber nicht, bzw. nur in stark vereinfachter Form vorhanden. In der vorliegenden Arbeit wurde die Wärmeübertragung für die komplexe Geometrie "Tellerstapel" sowohl experimentell als auch mit Hilfe von Computersimulation bestimmt. Die Ergebnisse beider Methoden zeigen gute bis sehr gute Übereinstimmung. Des Weiteren wurde der Wärmeübergang durch Strahlung mit in die Simulation einbezogen und sein Verhältnis gegenüber dem konvektiven Wärmeübergang ermittelt. Für die Wärmeübergangsberechnung bei anderen Geometrien gestapelter Güter wurden mehrere Wege aufgezeigt und auf die zeit- und kostensparende Nutzung moderner Simulationsmethoden hingewiesen.

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A detailed study is made on the luminescence of Pb('2+) ions in alkali halide single crystals. The emission spectra of KX:Pb('2+) (X = Cl, Br, I) excited in the A-absortpion band at various temperatures are reported. In addition, the excitation spectra of the A-band emission measured at 4.2 and 78 K are also given. The temperature dependence and the effect of an external magnetic field on the decay time of the A-band emission from KX:Pb('2+) is also investigated. / The results are interpreted in terms of a model that includes the Jahn-Teller effect, the spin-orbit interaction and an additional perturbation caused by the charge compensating cation vacancy (CV, v(,c)('-)). In this model, the Jahn-Teller effect is much smaller than the spin-orbit interaction and the CV is smaller still. The experimental results for KX:Pb('2+) are well in accord with this model. / The angular dependence of the polarization of the A-band emission from KX:Pb('2+) confirms that the Pb('2+) - v(,c)('-) pair is located on the C(,4) crystallographic axis. The temperature dependence of the polarization is treated within the framework of the above model in terms of the nonradiative processes between the relaxed excited states.

Ngaromoana Raureti Tomoana is a painter from the East Coast of the North Island. In more than 30 years she has produced and shown a large body of work, like many other women artists concurrently juggling motherhood and artistic performance. Over approximately the last 10 years, she has formalized her education completing the Advanced Diploma for Maori Visual Arts at Toihoukura in Gisborne as well as a Bachelor of Arts and a Masters of Maori Visual Arts at Massey University. The artist, who identifies as an Indigenous Village Artist, is hardly known outside her local area of Northern Hawkes Bay, and, apart from a short feature in Mataora , a picture in Te Ata , and various catalogue entries, little has been written about her work. This thesis introduces Ngaromoana Raureti Tomoana and explores the notion of an indigenous village art. I incorporate feminist and postcolonial discourses into a political and critical engagement with her art, which addresses issues of village and land based cultural identity as well as race and gender. I argue that her work is politically motivated and important in the context of contemporary Maori art. Furthermore, based on a holistic world view, it simultaneously reaches out into the wider, global community. Intertwining local and personal history, her oeuvre is the manifestation of a female path and a female perspective, of identification with her village and beyond.

The resurgence of interest in properties of molecules of icosahedral symmetry follows the discovery of the C₆₀ molecule. Due to the high symmetry of the icosahedron, almost all the electronic and vibrational levels are highly degenerate, so that in dealing with properties of these systems, the Jahn-Teller interaction must almost always be allowed for. This thesis primarily explores the properties of the icosahedral G ⊗ (g ⊕ h] interaction and related subsystems in the strong coupling régime. Mappings of the adiabatic potential energy surfaces facilitate an analysis of the geometrical phase or Berry phase acquired by the quantal system on transportation around adiabatic circuits in parameter space. The Berry phase information in conjunction with an analysis of tunnelling, determines the properties of the ground state. The use of Ham factors achieves a characterization of the various coupling régimes. However, characterization of G and H Jahn-Teller systems, requires an extension of the standard definition of these Ham factors. In such cases the extended matrix elements between and within vibronic tunnelling sublevels cannot be ignored. A calculation of all the standard and extended matrix elements is presented. A further introduction of a matrix of Ham factors facilitates the description of H multiplicity within an H manifold. Finally, two problems are investigated numerically; aimed at making some allusion towards possible experimental manifestations of G ⊗(g(⊕)h). The first investigation considers the variations in the eigensystem and Ham factors of G ⊗ (g ⊕ h), as a function of the coupling to the two modes. The second investigation considers the structure in the optical absorption line shapes for the transitions from orbital singlet to quartet, G, states in an icosahedral environment. The quartet states are subject to both spin-orbit and linear Jahn-Teller interactions.

Stuttgart, Univ., Diss., 2006.

Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Document formatted into pages; contains xv, 323 p.; also includes graphics (some col.) Includes bibliographical references. Available online via OhioLINK's ETD Center

Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 280-284).

Various gold complexes were computationally investigated, to probe their photophysical, geometric, and bonding properties. The geometry of AuI complexes (ground state singlet) is very sensitive to the electronic nature of the ligands: σ-donors gave a two-coordinate, linear shape; however, σ-acceptors yielded a three-coordinate, trigonal planar geometry. Doublet AuIIL3 complexes distort to T-shape, and are thus ground state models of the corresponding triplet AuIL3. The disproportionation of AuIIL3 to AuIL3 and AuIIIL3 is endothermic for all ligands investigated, however, σ-donors are better experimental targets for AuII complexes. For dimeric AuI complexes, only one gold center in the optimized triplet exciton displays a Jahn-Teller distortion, and the Au---Au distance is reduced versus the ground state distance (i.e., two reasons for large Stokes' shifts).