Dynamic polarizability of small metal particles

Abstract
A simplified treatment of the random-phase-approximation dynamic polarizability of small metal particles is presented. Assuming that the self-consistent polarization potential takes its classical form, the electron-hole pair excitation rate is calculated in the limit of large particle radii and is related, through the average power absorption, to the dynamic polarizability. Both collective and single-particle aspects are treated in a consistent fashion. For a jellium model the method is shown to reproduce the main features of more elaborate time-dependent density-functional-theory calculations. One advantage of the present approach is that it can be generalized and applied to more realistic models of metal particles.