FIRST-PRINCIPLES DETERMINATION OF THE INTERATOMIC-FORCE-CONSTANT TENSOR OF AU

Using the plane-wave-based linear response method recently developed, the interatomic-force-constant tensor for the noble metal Au is obtained. Using an optimized pseudopotential to model the ion-electron interaction requires only a modest number of plane waves, and the calculated phonon dispersion curves are in excellent agreement with experiment. The force constant tenser is studied in detail and is compared with those obtained from Born-Von Karman fits to the experimental Excellent agreement with experiment is found when the range of interaction is taken to fourth neighbors, however, longer-ranged interactions need to be included to accurately determine the lattice specific heat.