No description available.

No description available.

(La0.67Sr0.33MnO3)£»(SrO), LSMO214(n=1) in short, is 2-D magnetic insulator with a structure very similar to the 3D La0.67Sr0.33MnO3 and La0.67Ca0.33MnO3, 113(n=1) in short, which consists of superstructure of a subsequent magnetic layers and insulating layers. Forming a single 214 phase bulk is not easy, a mix phase of 2<n<¡Û compounds is usually seen. In this project, our goal is to search the best growth condition by the traditional method by varying one growth parameter at a time and by the famous Taguchi methods which is based on the statistics and is proved in many systems a best way in studying the association between the film properties and the control factors. First part of this project, we change one growth condition at a time and find the film quality related with the growth condition. Second, we use ¡§Taguchi method¡¨ as bases to form a perpendicular table in which various growth conditions and levels are set. According the table, the number of experiments is limited down to nine. All of the films are examined by structure, electric and magnetic properties to formed the quality data base for films. The traditional method concludes that the higher growth temperature, lower total chamber pressure and high partial pressure ratio of Ar and Oxygen are the corrected way approaching to the single phase, 214, films. However, the result from Taguchi method is contradict to the tradition method, in which the high growth temperature, high total chamber pressure, low partial pressure ratio of Ar and oxygen and the medium RF forward power can approach to growth the single 214 phase film. All films consists mix phases of higher n. This may imply that the growth window for LSMO 214 is relative narrow that we did not set our condition right in that opening.

This dissertation deals with two major topics that involve spectroscopic studies of (a) divalent group 10 metals and (b) silver(I)-phosphine complexes. The scope of the work involved the delineation of the electronic structure of these complexes in different environments and their use in electronic devices. The first topic is a look at the luminescence of tetrahedral silver(I)-phosphine complexes. Broad unstructured emissions with large Stokes shifts were found for these complexes. Computational analysis of the singlet and triplet state geometries suggests that this emission is due to a Jahn-Teller type distortion. The second topic represents the major thrust of this research, which is an investigation into the electronic structure of M(diimine)X2 (M= Pt(II), Pd(II), or Ni(II); X = dichloro, or dithiolate ligands) complexes and their interactions with an electron acceptor or Lewis acid. Chapter 3 assesses the use of some of these complexes in dye sensitized solar cells (DSSCs); it is shown that these complexes may lead to a viable alternative to the more expensive ruthenium-based dyes that are being implemented now. Chapter 4 is an investigation into donor/acceptor pairs involving this class of complexes, which serves as a feasibility test for the use of these complexes in organic photo-voltaics (OPVs) and thin-film field-effect transistors (OTFTs). The mixing of a donor Pt molecule with an electron deficient nitrofluorenone gives rise to new absorption bands in the NIR region. Computational studies of one of the solids suggest that these complexes may have metallic behavior. Chapter 5 demonstrates association in solution, previously unobserved, for Pt(diimine)Cl2 complexes. This chapter is an investigation into the effects of the association mode for this class of complexes on the absorption and emission properties. One of the complexes was used as the emitter in organic light emitting diodes (OLEDs). The results of this study show that these complexes have tunable absorption and emission energies that are concentration dependant. The concentration dependence of the absorption and emission energies is utilized in the OLED device where association enhances the performance.