A series of para-dioxolene bridging ligands with bis-tridentate or bis-bidentate coordination pockets have been prepared. These ligands were designed to serve as building blocks in the preparation of functional metallosupramolecular structures. The bis-tridentate dipyridyl-diazaanthraquinones have topologies suitable for the preparation of [2 x 2] grids or larger extended structures. Employing a double condensation reaction between 1,3-diamino-4,6-benzenedicarboxaldehyde and 2-acetyl pyridine successfully afforded a cisoid binding diazaanthraquinone. The redox activity of the latter revealed it is more easily reduced than structurally similar 1,5- and 1,8-diazaanthraquinones. The synthesis of an analogous ligand displaying transoid coordination pockets proved challenging. Several approaches were attempted however the preparation of key intermediates 1,4-dinitro-2,5-benzenedicarboxaldehyde and 2,5-diamino-1,4-(hydroxyI-methyl) benzene were unsuccessful. A collection of bis-bidentate 2,5-bis(phosphino)1,4-dioxolenes were prepared with diphenyl, diisopropyl and diethoxy substituents at the phosphorus center. 2,5- Dibromo-1,4-dimethoxybenzene was reacted with the appropriate chlorophosphine under lithiation conditions to afford the dimethoxy compound, which was subsequently deprotected to the hydroquinone state with a Lewis acid. The diphenylphosphino hydroquinone was oxidized using phenyliodonium bisacetate, however efforts to oxidize other hydroquinone precursors to the targeted quinone state proved challenging. Diphenyl and diisopropyl phosphino hydroquinones were successfully coordinated with diamagnetic palladium hexafluoroacetylacetonate precursors. The resulting bimetallic bis(phosphino) dianion complexes were subsequently oxidized to the semiquinone state using silver (I) hexafluorophosphate and studied to determine the distinctive features of the semiquinone ligand.

The magnetic spinel ferrite nanoparticle is exceptionally intriguing nanocrystal system due to the industrial importance of various technical applications and the scientific significance of studying the quantum origin of magnetism. Studies of quantum influences upon magnetic properties have revealed that the spin-orbit coupling and the net magnetization greatly affect the net magnetic properties of each spinel ferrite system differently. In case of cobalt ferrite where spin-orbit coupling is relatively large, increasing Cr3+ doping concentration, which has smaller magnetic moment and zero angular moment, decreases blocking temperature, saturation magnetization, remnant magnetization and coercivity. However, in case of manganese ferrite where spin-orbit coupling is relatively small, increasing Cr3+ doping concentration, reduces all the magnetic parameters except coercivity. The coercivity increases due to smaller magnetocrystalline anisotropy energy constant which forces the coercivity to increase as saturation magnetization decreases in accordance with Stoner-Wohlfarth theory. In order to improve product quality and quantity, synthesis routes in hot oleylamine and aminolytic reaction were developed. Both methods were proven to be extremely effective, environmental friendly, inexpensive, and simple routes in the synthesis of a variety of spinel ferrite systems including CoFe2O4, MnFe2O4, NiFe2O4, and ZnFe2O4 from a single source metal precursor.

Thesis (Ph.D.)--McMaster University (Canada), 1991. / Source: Dissertation Abstracts International, Volume: 54-02, Section: B, page: 0847.

Thesis (Ph. D.)--Materials Science and Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Dr. C. P. Wong; Committee Co-Chair: Dr. Manos Tentzeris; Committee Member: Dr. Hamid Garmestani; Committee Member: Dr. Meilin Liu; Committee Member: Dr. Z. L. Wang.

Thesis (Ph.D.)--University of Delaware, 2009. / Principal faculty advisor: John Q. Xiao, Dept. of Physics and Astronomy. Includes bibliographical references.

Thesis (Ph.D.) - University of St Andrews, March 2008.

Thesis (Ph.D.)--University of Texas at Dallas, 2008. / Includes vita. Includes bibliographical references.

Thesis (Ph. D.)--Florida State University, 2004. / Advisors: Dr. Naresh Dalal, Dr. Johan van Tol, Florida State University, Arts and Sciences, Dept. of Chemistry and Biochemistry. Title and description from dissertation home page (viewed Jan. 18, 2005). Includes bibliographical references.

Thesis (M.S.)--University of Texas at El Paso, 2009. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.

Μελετάμε, χρησιμοποιώντας υπολογισμούς ηλεκτρονικής δομής από πρώτες αρχές, τις μαγνητικές ιδιότητες διάφορων κραμάτων (BiFeO3, BiMnO3 και Bi2MnFeO6) και πολυστρωμάτων είτε με ημιαγώγιμο υπόστρωμα (InP/BiFeO3) είτε με υπόστρωμα μετάλλων μετάβασης (V/BiFeO3 και Fe/BiFeO3). Όλα τα κράματα και τα πολυστρώματα τα οποία μελετήθηκαν είχαν δομή σφαλερίτη (zinc – blend). Τα υλικά αυτά ανήκουν στην κατηγορία των μαγνητοηλεκτρικών υλικών, μία κατηγορία με έντονο επιστημονικό ενδιαφέρον λόγω των πολλαπλών πλεονεκτημάτων που παρουσιάζει η χρησιμοποίησή τους σε μαγνητοηλεκτρικές εφαρμογές, π.χ. σε σκληρούς δίσκους και σε μνήμες ηλεκτρονικών υπολογιστών. Τα παραπάνω υλικά μελετήθηκαν για διαφορετικές μαγνητικές δομές. Για το BiFeO3 θεωρήσαμε τρεις πιθανές αντισιδηρομαγνητικές διαμορφώσεις και την σιδηρομαγνητική λύση. Επίσης μεταβάλαμε την πλεγματική σταθερά της μοναδιαίας κυψελίδας από 5.6 a.u. έως και 8.1 a.u.. Για το BiMnO3 μελετήθηκαν τρεις αντισιδηρομαγνητικές και μία σιδηρομαγνητική διαμόρφωση για δύο τιμές της πλεγματικής σταθεράς: 14 a.u. (ή 3.703 Å) και 14.7 a.u. (ή 3.888 Å). Για το Bi2MnFeO6 υπάρχουν τρεις διαφορετικές περιπτώσεις ανάλογα με τις θέσεις των ατόμων Fe και Mn, και για κάθε περίπτωση έχουν μελετηθεί πέντε αντισιδηρομαγνητικές διαμορφώσεις και μία σιδηρομαγνητική, για τις ίδιες πλεγματικές σταθερές με το BiMnO3. Στα πολυστρώματα InP/BiFeO3 υπάρχουν τέσσερις περιπτώσεις των οποίων η διαφορά βρίσκεται στις θέσεις των ατόμων In και P στο υπόστρωμα. Τέλος, στα πολυστρώματα V/BiFeO3 και Fe/BiFeO3 μελετήθηκαν πέντε διαφορετικές περιπτώσεις, των οποίων η διαφορά εντοπίζεται στην πλεγματική σταθερά. Οι προσομοιώσεις μας έδειξαν ότι ενώ τα κρυσταλλικά κράματα παρουσιάζουν έντονες μαγνητικές ιδιότητες, στην περίπτωση των πολυστρωματικών υμενίων, η μείωση σε διαστάσεις οδηγεί σε σημαντική υποβάθμιση των μαγνητικών ιδιοτήτων και σε μερικές περιπτώσεις σε σχεδόν μη – μαγνητικές λύσεις. / We study, using first – principles electronic structure calculations, the magnetic properties of various alloys such as BiFeO3, BiMnO3, Bi2MnFeO6 and multilayers with a semiconducting (InP/BiFeO3) or a transition metal (V/BiFeO3 and Fe/BiFeO3) substrate. All the previous alloys and multilayers have a zinc – blend structure. These materials are known as magnetoelectric materials, a category which has attracted intense scientific interest due to the advantages of implementing these materials in spintronic devices e.g. computer's hard disks and RAM memories. These materials were studied for various magnetic structures. For BiFeO3 we considered three antiferromagnetic and a ferromagnetic configurations. We also varied the lattice constant of the unit cell from 5.6 a.u. to 8.1 a.u.. For BiMnO3 we studied three antiferromagnetic and one ferromagnetic configurations for two values of the lattice constant: 14 a.u. (or 3.703 Å) and 14.7 a.u. (or 3.888 Å). For Bi2MnFeO6 there are three different cases depending on the positions of Fe and Mn atoms, and in each studied case five antiferromagnetic and one ferromagnetic configurations were taken into account, concerning InP/BiFeO3 multilayers there are four cases where the difference concern the positions of In and P in the substrate. Finally, the multilayers V/BiFeO3 and Fe/BiFeO3 were studied for five different values of the lattice constant. Our simulations show that although the bulk alloys exhibit considerable magnetic properties, the latter are seriously downgraded for multilayers and in same casses magnetism almost vanishes.