Ab Initio Evaluation of Plasmon Lifetimes in the Alkali Metals
  The anomalous plasmon linewidth dispersion (PLD) measured in K by vom Felde, Sprosser-Prou, and Fink (Phys. Rev. B 40, 10181 (1989)), has been attributed to strong dynamical electron-electron correlations. On the basis of ab initio response calculations, and detailed comparison with experiment, we show that the PLD of K is, in fact, dominated by decay into particle-hole excitations involving empty states of d-symmetry. For Li, we shed new light on the physics of the PLD. Our all-electron results illustrate the importance of ab initio methods for the study of electronic excitations. 
Wei Ku (1) and Adolfo G. Eguiluz (1 and 2) ((1) Department of Physics   and Astronomy, The University of Tennessee, Knoxvill...