Research in the fields of molecular conductors and magnets over the past four decades has involved collaborative efforts of chemists and physicists whose common goal is to design useful materials composed of molecular building blocks. Of particular interest are materials whose properties can be tuned by electronic or steric changes in the molecular sub-units. The research on TCNQ derivatives described in this thesis was inspired by the observation that, although a vast amount of research has been directed at understanding binary M(TCNQ•-) materials, analogous compounds based on substituted TCNQ acceptors are surprisingly scarce. Single crystals of a new structure type for the M+(TCNQ)•- binary family were isolated from reactions of two dihalogenated TCNQ derivatives with Cu(I) ions, namely Cu(TCNQX2) (X = Cl, Br). The new 3-D compound Cu(TCNQCl2) exhibits the highest conductivity of the M+(TCNQ)•- series to date, despite the greater separation of TCNQCl2 units as compared to other derivatives. Compounds of lower dimensionality were also obtained, namely the 2-D Cu(TCNQBr2)(CH3CN) and 1-D Cu(TCNQI2)(CH3CN)2 phases. Several 2p-3d heterospin molecular magnets were also synthesized. For example a “magnetic sponge” material based on a 2-D hexagonal framework of composition {[Mn2(TCNQF4)(CH3OH)7.5(H2O)0.5]-(TCNQF4)2•7.5CH3OH}∞, as well as molecular magnets based on first row metal ions and TCNQF4 ligands of composition MII(TCNQF4)-•(TCNQF42-)0.5(CH3CN) (M = Mn, Co) were prepared. In addition, unprecedented isostructural 2-D frameworks based on combinations of first row metal ions with TCNQBr2 radicals of composition [M(TCNQBr2)2(H2O)2]∞ (M = Mn, Zn) were synthesized. Lanthanide chemistry is also described in this dissertation. A series of mononuclear Ln-TCNQF4 heterospin complexes of composition {MIII[TCNQF4]2[H2O]x}(TCNQF4)(3H2O) (M = La, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er and Yb) was also obtained which exhibit remarkable properties. In this family of compounds there exists an unprecedented subtle interplay between single molecule magnetic behavior and phonon bottleneck effect behavior for the Tb analogue. Magnetic ordering was observed for the Sm analogue. A homologous series of 1-D materials based on alternating lanthanide ions and hexacyanometallates of formula {[Ln(tptz)(H2O)4Fe(CN)6]•8H2O}∞ (Ln = Pr, Nd, Sm, Eu, Gd, Tb) was obtained and a detailed magnetic study provided incontrovertible evidence that the SmIII-[FeIII(CN)6]3- compound exhibits ferromagnetic and not antiferromagnetic coupling as had been reported for related 1-D chains.

Thesis (D.M.A.)--University of Illinois at Urbana-Champaign, 2007. / Includes abstract. Vita. Source: Dissertation Abstracts International, Volume: 69-02, Section: A, page: 0433. Adviser: Chester L. Alwes. Includes bibliographical references (leaves 137-144) and discography (leaves 127-130). Available on microfilm from Pro Quest Information and Learning.

Thesis (D.W.S.)--Institute for Worship Studies, 2002. / Abstract. Includes bibliographical references (leaves 157-162).

Since their discovery, organic electronic materials have been of great interest as an alternative active layer material for active area materials in electronic applications. Initially studied as probes or lasing material the field has progressed to the point where both conjugated polymers and small organics have become fashionable objects of current device oriented solid state research. Organic electronic materials are liquid crystalline materials, packing into well-ordered domains when annealed thermally or via solvent annealing. The macromolecular orientation of the molecules in the solid state causes a shift in the electronic properties due to coupling of the dipoles. The amount of interaction between molecules can be correlated to different nanoscale morphologies. Such morphologies can be measured using microscopy techniques and compared to the spectroscopic results. This can then be extrapolated out to infer how the charges move within a film. Cyanine dyes represent an interesting form class of dyes as the molecular packing is strongly affected by hydrophilic and hydrophobic pendent groups, which cause the dye to arrange into a tubular bilayer. Spectroelectrochemistry is used to monitor and controllably oxidize the samples. Using singular value decomposition (SVD) it is possible to extract each electronic species formed during electrochemical oxidation and model the proposed species using semi empirical quantum mechanical calculations. Polyfluorene is a blue luminescent polymer of interest for its high quantum yield. The solution and solid-state conformation has shown two distinct phases. The formation of the secondary phase shows a dependence on the molecular weight. In a poor solvent, as the molecular weight increases, the secondary phase forms easier. In the solid state, the highly efficient blue emission from polyfluorene is degraded by ketone defects. The energy transfer to preexisting ketone defects is increased as the filmed is thermally ordered. Glass transitions of block copolymers are studied using synthetically novel polymers where an environmentally sensitive fluorescent reporter is placed within various regions of a self-assembled film. Different dynamics are observed within the block of the film then specifically at the interface of two blocks. / text

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The main objective of the present work was the systematic study of BaSn1-xMxO3-d (M = Y, Gd, Sc, In, ...) as proton conductors. We first developed a synthesis route based on the acrylic acid polymerization. This allowed us obtaining pure nanopowders and dense ceramics after a classical sintering process. We then studied the influence of dopant nature and content on the structural and electrical properties. This study was coupled to theoretical calculations which helped us predicting the most probable defects within the structure. Results indicate that the substitution model is closely linked with dopant size. For small cations, the substitution on B-site occurs as foreseen by the original compound formula. For big cations (La, Nd and Sm), the modeling anticipates a possible partial substitution on A-site, confirmed by an anomaly observed on the evolution of cell parameters. Concerning electrical properties, we did not observe any significant trend as a function of dopant size. It seems nevertheless that best dopants in terms of anion or proton conduction are those presenting the smaller dopant-defect interaction energy as revealed by semi-empirical calculations. In the case of yttrium, the evolution of conduction with Y3+ content is linked both to the increase of charge carriers due to doping and to the increase of grain size with increasing dopant content. We also showed that the stability is strongly linked with the doping level. While highly doped compounds are unstable in humid atmosphere, slightly doped compounds present good stability in humid, hydrogen and CO2 containing atmosphere. Finally, we showed that ZnO as an additive could be used to lower the sintering temperature without changing the conduction properties. This study thus showed that BaSn1-xMxO3-d(M = Y, Gd, Sc, In, ...) may find applications as proton conductors if dopant level is limited for stability reasons, grain size important for better conduction properties and the elaboration process optimised to ensure high density.

Dr. Eph Ehly is one of the most sought after choral conductors in the United States today. Ehly has conducted over seventy All-State choirs. However, no previous source outlines the fundamental principles of his philosophy and rehearsal techniques.This study was designed to capsulize Ehly's contributions. The writer produced a videotape entitled, "Eph Ehly: A Source of True Inspiration." This video captures Dr. Ehly's philosophy regarding the All-State choir experience and demonstrates his rehearsal techniques. The author attended three All-State festivals where Ehly was the guest conductor (Indiana, New York, and Oklahoma). The video contains rehearsals and performances and videotaped interviews with Dr. Ehly.The cornerstone of Ehly's approach is this: using music to express. There are three components to Ehly's philosophy: 1) the physical component, 2) the emotional component, and 3) the spiritual component. The writer identified four forms of the physical component: 1) handshake, 2) hug, 3) clapping, and 4) other spontaneous physical gestures. The writer identified eight aspects of the emotional component: 1) expressivity, 2) sensitivity to the world, themselves, and their own emotions, 3) sympathy, 4) reality of emotions, 5) creating mood, 6) building ensemble, 7) music as a reflection of life, and 8) awareness of a "sixth sense." In describing the spiritual component, two divisions were identified: 1) the development of character, and 2) reaching a level of spirit-awareness.The study also summarizes Ehly's rehearsal techniques by outlining his idiosyncratic approach to the treatment of traditional musical elements. The video presentation highlights nine technical concerns and demonstrates Ehly's approach to these common problems. The areas addressed are: 1) tone quality, 2) diction, 3) rhythm, 4) dynamics, 5) phrasing, 6) articulation, 7) breathing, 8) vowel modification, and 9) vibrato. The videotape is supported by a written document containing background information, a script of the video, a summary by the author, a representative list of programs from AllState choirs conducted by Dr. Ehly, and transcripts of the interviews with Dr. Ehly. Church musicians, professional conductors, educators, and students of conducting can all benefit from the opportunity to view and evaluate Ehly's approach. / School of Music

The purpose of this study is to determine the influence of scholarly research on the orchestral performance practice of conductor Raymond Leppard.This study presents, with supporting evidence, what an international conductor does today to incorporate the results of research into the interpretation of music. From this study, the writer has presented the influence scholarly research has had on orchestral performance practice, how one of today's conductor and orchestras deal with the issues raised and how they are carried into current performances, and to what degree do musicologists influence his performance. Orchestra conductors continue to learn from performance practice research and young conductors must be encouraged to gain knowledge from this field.Three scholarly musicians, Arnold Dolmetsch (1858-1940), Edmund H. Fellowes (1870-1951), and Thurston Dart (1921-1971), among many others, did much to revive authentic performances of earlier music. Their critical and historical writings are based on original sources and the concept of interpretation by studying composers' original manuscripts and editions in order to better present their musical style and heritage. This developed a strong movement towards the study of incorporating authentic music research into music performance.Maestro Leppard is known particularly for his interpretations of seventeenth and eighteenth century music. He prepared the revivals of Monteverdi and Cavalli's Italian operas. Maestro Leppard has had many experiences with European and American orchestras and has made many recordings. The contents of the interview focused on (1) orchestra size and seating, (2) the authenticity of music, (3) some basic performance practice elements such as tempo, rhythm, dynamics, articulation and phrasing, ornamentation, vibrato, and portamento, (4) string bowing, (5) editions, and (6) interpretation and personal observations. / School of Music

Pinning landscapes in modern second generation coated conductors are excellent candidates for studies of vortex pinning. The ability to produce engineered defects in thin films of high temperature superconductors allows one to investigate representative distinct pinning sites, with the objective of understanding how different pinning centers contribute, compete and evolve under varying conditions of magnetic field strength and orientation, and temperature.New contact-free methods were developed specifically to investigate this system in new ways, especially the dependence of the critical current density Jc on orientation of the magnetic field. A superconducting quantum interference device (SQUID)-based magnetometer was used to determine angular critical current density profiles. The induced currents produced in contact-free methods allow one to investigate a range of temperatures that is difficult to access by traditional transport measurements.Materials with three distinctive pinning landscapes were investigated: Specifically, samples were studied that were dominated by columnar defects, by isotropic defects, or a mixture of these two types of pins. These studies over an expanded temperature-field-orientation phase-space clearly show competition between not only strong and weak pinning centers, but also between the angularly selective and nonselective pinning. This evidence is seen in critical current density profiles, the α [alpha]-values describing the falloff of Jc with magnetic field, and matching field effects in the three samples studied.