Electronic stopping power from time-dependent density-functional theory in Gaussian basis

Abstract

The electronic stopping power, which is the energy transfer from a charged particle travelling through a material to the electrons of the material, has attracted much attention back from the early beginnings of quantum mechanics. It requires the description of the electronic excitations taking place in the target material and has been limited to model systems for a long time. With the advent of time-dependent density-functional theory (TDDFT), it is nowadays possible to provide a complete and realistic quantum-mechanical description of the phenomenon. We present here an implementation of TDDFT based on Gaussian basis for finite systems. The localized Gaussian basis has numerous advantages, such as the cheap account of core electrons, the simple implementation of the modern hybrid functionals, and the possibility of a tunable basis accuracy as a function of space. With our tool, we explore the bulk limit, the validity of the impact parameter averaging to obtain the experimental random electronic stopping power, and the connection to the simpler linear-response results for lithium metallic clusters for different ionic projectiles.