Drude Model for the Optical Properties of a Nano-Scale Thin Metal Film Revisted Jeong Su Yang, Seung Gol Lee, Se-Geun Park, El-Hang Lee and Beom-Hoan O J. Korean Phys.Soc. 55,2552 [doi: 10.3938/jkps.55.2552 | PDF Download] This study proposes a modified Drude model to understand theanomalous behavior near the visible spectrum region. The proposedmodel contains the novel elastic collision parameter $\gamma^\prime$in a dielectric function in the description of the boundaryscattering of free electrons and electron-electron interactionswithin metallic nano-sized quasi-clusters in which the dampingconstant $\gamma$ of the conventional Drude model is notexaggerated. The proposed model also provides impressive data fitsfor the dielectric function measured by Johnson and Christy.