Molecular dynamics simulations were used to study the scattering of phonon wave packets of well-defined frequency and polarization from individual point defects and from a field of point defects in Si. The relative amounts of energy in the transmitted and reflected phonon fields were calculated and the parameters that influence the phonon scattering process were determined. The results showed that the fractions of transmitted and reflected energies depended strongly upon the frequency of the incident phonons and upon the mass and concentration of the defects. These results were compared with the classic formula for the scattering strength for point defects derived by Klemens, which was found to be valid when each phonon-defect scattering event was independent. The Klemens formula failed when coupled multiple scattering predominated. The phonon density of states was used to characterize the effects of point defects on mode mixing.Phonon-Defect Scattering in Doped Silicon by Molecular Dynamics Simulation. M.Yao, T.Watanabe, P.K.Schelling, P.Keblinski, D.G.Cahill, S.R.Phillpot: Journal of Applied Physics, 2008, 104[2], 024905