Table of Contents
Advances in Optics
Volume 2014, Article ID 814909, 9 pages
Research Article

A Theoretical Study of Bulk Tungsten (W) Based on Momentum Transfer (-Dependent)

Department of Physics, Mizoram University, Aizawl 796004, India

Received 7 May 2014; Revised 28 July 2014; Accepted 25 August 2014; Published 8 October 2014

Academic Editor: Marco Consales

Copyright © 2014 D. P. Rai and R. K. Thapa. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The ground state electronic properties of bulk (W) were studied within the density functional theory (DFT). We have also analyzed the momentum- (q-) dependent loss function, dielectric constant, and optical conductivity (OC) within TD-DFT random-phase approximation (RPA). The loss function is plotted in the energy range 0–55 eV. The energy loss function spectrum shows four prominent peaks, two lower peaks below along with two sharp peaks above 30 eV. The different nature of peaks depends on the momentum transfer q. The peak caused by interband transition showed a less pronounced dispersion. From the dielectric function curve we have predicted the plasmon excitation at around 1.75 eV and calculated the corresponding plasma frequency  s−1.