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تسجيل مستخدم جديدTime-Dependent Density-Functional Theory for the Stopping Power of an Interacting Electron Gas for Slow Ions
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Based on the time-dependent density-functional theory, we have derived a rigorous formula for the stopping power of an {it interacting} electron gas for ions in the limit of low projectile velocities. If dynamical correlation between electrons is not taken into account, this formula recovers the corresponding stopping power of {it noninteracting} electrons in an effective Kohn-Sham potential. The correlation effect, specifically the excitonic one in electron-hole pair excitations, however, is found to considerably enhance the stopping power for intermediately charged ions, bringing our theory into good agreement with experiment.
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Due to the strongly nonlocal nature of $f_{xc}({bf r},{bf r},omega)$ the {em scalar} exchange and correlation (xc) kernel of the time-dependent density-functional theory (TDDFT), the formula for Q the friction coefficient of an interacting electron g
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