Silicon's material properties, have been studied extensively because of its technological significance in a variety of industries, including microelectronics. Yet, questions surrounding the phonon relaxation times in silicon continue to linger.1,2 Previous theoretical works3-5 have generated qualitative expressions for phonon relaxation times, however these approaches require fitting parameters that cannot be determined reliably. This paper first discusses implementation issues associated with using the Green-Kubo method in molecular dynamics (MD) simulations. We compare various techniques used in similar works and discusses several implementation issues that have arisen in the literature. We then describe an alternative procedure for analyzing the normal modes of a crystal to extract phonon relaxation times. As an example material we study bulk crystalline silicon using equilibrium MD simulations and lattice dynamics. The environment dependent interatomic potential6 is used to model the interactions and frequency dependent phonon properties are extracted from the MD simulations.
Anharmonic lattice dynamics ofAg2Ostudied by inelastic neutron scattering and first-principles molecular dynamics simulations