Predicting the Lattice Thermal Conductivity in Nitride Perovskite LaWN₃ from ab initio Lattice Dynamics.

ABSTRACT: Using a density functional theory-based thermal transport model, which includes the effects of temperature (T)-dependent potential energy surface, lattice thermal expansion, force constant renormalization, and higher-order quartic phonon scattering processes, it is found that the recently synthesized nitride perovskite LaWN₃ displays strong anharmonic lattice dynamics manifested into a low lattice thermal conductivity (κ_L ) and a non-standard κ_L ∝T^-0.491 dependence. At high T, the departure from the standard κ_L ∝T^-1 law originates in the dual particle-wave behavior of the heat carrying phonons, which includes vibrations tied to the N atoms. While the room temperature κ_L =2.98 W mK^-1 arises mainly from t

SUBMITTER: Tong Z 

PROVIDER: S-EPMC10037690 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature