| The prospect of precisely predicting the behavior of solids entirely by means of theory and computations is enticing. This dissertation presents the results of the application of the first-principles physical approaches to study superconductivity in a set of materials. In the first chapter a brief overview of the key concepts used in this manuscript in given. A description of the theoretical methodology and the key computational techniques used in this work constitute the subject of chapter 2. Studies of class-I/conventional and class-II/non-conventional superconducting materials are contained in chapters 3 and 4 respectively. In particular, precise calculations of the electron-phonon interaction and superconducting parameters of elemental lithium at ambient conditions and under pressure and lithium-intercalated borocarbide compounds are presented. In addition, the application of first-principle techniques to study iron selenide in multiple configurations is given. A discussion of superconductivity in complex oxides is presented in chapter 5 with emphasis on the importance of oxygen octahedra tilts. And, finally, concluding remarks from the author are given in the last chapter. |
