Low frequency plasmon spectra in stage I and stage II FeCl 3 intercalated graphite

Abstract

Theoretical analyses of plasmon lineshapes and dispersion in model stage I and stage II graphite intercalation compounds (GIC's), with application to FeCl 3 intercalated graphites are presented. From a general analytic model of the longitudinal dielectric response functions we discuss the electronic properties of graphite intercalation compounds which are effectively probed in inelastic electron scattering spectra below 3 eV. Band structure and local field effects are then explicitly included in numerical calculations of energy loss spectra in these compounds. We note that band structure effects are very significant in determining plasmon dispersion and damping in these compounds, and find that a model band structure with band parameters extracted from previous studies of pristine graphite provides a good description of the observed spectra.