Calcul semi-empirique de la temperature de transition des superconducteurs et de l'effet de la pression sur la transition

A method is developed to take into account the contribution of the Umklapprozesse to the electron-phonon interaction in polyvalent metals. This method is used to compute—from first principles—the high-temperature resistivity of non-transition metals as well as the transition temperature T_c of non-transition superconductors along the lines of Bardeen, Cooper and Schrieffer's theory of superconductivity (Phys. Rev. 108, 1175 (1957)). The effect of pressure on T_c is also computed and its dependence upon the band structure is stressed.