Korea

The thermal conductivity of the Lennard-Jones argon crys-tal is predicted using the Boltzmann transport equation under the single mode relaxation time approximation. The temperature and frequency dependence of the phonon dispersion and phonon re-laxation times are obtained from lattice dynamics calculations based on the results of molecular dynamics simulations. No fit-ting parameters are required. The thermal conductivity results are in agreement with predictions from the simulations using the Green-Kubo method. Assuming that the dispersion is linear or temperature independent, as is often done in analytical calcula-tions, leads to large errors in the predictions. This result suggests that the fitting parameters required in such calculations offset sig-nificant errors introduced by these simplifying assumptions