Phonon spectral energy density analysis of solids: The k point reduction in the first Brillouin zone of FCC crystals and a case study on solid argon

摘要

Many crystals of scientific and technical importance have the face-centered cubic (FCC) lattice. Computational studies of electronic, thermal, and optical properties of FCC crystals usually involve the first Brillouin zone. In this work, we examine the geometry and discretization of the first Brillouin zone of FCC crystals. We report the coordinates of the high symmetry k points in the first Brillouin zone and a systematic way of determining the coordinates of the symmetry k points. We find that using the symmetry k points could reduce the total number of k points by as much as 97.92% and thus greatly reduce the computational cost. We propose a formula for calculating lattice thermal conductivity by using phonon properties at the symmetry k points. The formula is validated by calculating the thermal conductivity of solid argon in the temperature range from 10 to 80 K with the phonon spectral energy density (SED) method and comparing the results with those from equilibrium molecular dynamics (EMD) simulations and experiments. (C) 2016 Elsevier B.V. All rights reserved.