Theoretical study of lattice dynamics and thermal conductivity of LiF crystal

Abstract:

The lattice thermal conductivity of lithium fluoride (LiF) is accurately computed from a first-principles theoretical approach based on an iterative solution of the Boltzmann transport equation. Real-space finite-difference supercell approach is employed to generate the second- and third-order interatomic force constants. Then the related physical quantities of LiF crystal are calculated by the second- and third- order potential interactions at 30 K to 1000 K. The calculated lattice thermal conductivity 13.89 W/(m∙K) for LiF at room temperature agrees well with the experimental value, demonstrating that the parameter-free approach can furnish precise descriptions of the lattice thermal conductivity of this material.