Anharmonic Phonons in Complex Systems: Application to MgSiO3-Perovskite

We propose a strategy to capture phonon frequency renormalization due to phonon-phonon interactions included in molecular dynamics simulations (self-consistent phonons). This strategy is effective irrespective of crystal structure complexity and facilitates the Fourier interpolation of anharmonic frequencies throughout the Brillouin zone. Calculation of anharmonic frequency shifts in MgSiO$_{3}$-perovskite validates the method by reproducing well irregular thermal shifts measured by Raman spectroscopy at ambient conditions. \textit{Research supported by NSF/EAR}