Doping and phase transitions processes on semiconductors and vibrational properties in complex glasses: A theoretical and experimental investigation

Abstract

Bridging the gap between experimental and computational researchers by fostering close collaborations is mandatory for making a breakthrough in the investigation of materials. The combined forces of these two pillars, experiment and in-depth computational analyses are more powerful than ever and capable of quantitative predictions, though care must still be taken in comparing results from theory and experiment. It is the main strength of the present Ph. D, which cover a multidisciplinary field combining physics, chemistry, theoretical and computational chemistry, and materials science pushing the boundaries for find and understand the structure and properties, at atomic level, of two types of materials: glasses (Ba2SiO4, high-BaSiO3, Ba4Si6O16, Ba5Si8O21, Ba6Si10O26, high-BaSi2O5 and low-BaSi2O5) and semiconductors (PbMoO4, In2O3, ZrO2, CaWO4 and SnMoO4/SnWO4). We discuss and present recent advances for understanding, by the use of first-principles quantum-mechanical calculations, at DFT level, their structural, electronic, and optical properties. We also studied the doping processes, the formation of solid solution, and phase transitions induced by pressure, that play key roles in the further development of these materials for optoelectronic and photocatalytic applications. We hope that present results guide the synthesis for the most promising candidates of a particular application.