Study of the first-principles correlation functional in the calculation of silicon phonon dispersion curves
In this study, the latest published first-principles Chachiyo correlation functional has been implemented to obtain the phonon dispersion relation of silicon. The calculations are based on local-density approximation (LDA) within the plane-wave pseudopotential method. We obtain good agreement and sufficient accuracy results compared with the experimental data and phonon dispersion curves from the typical Perdew-Zunger functional. As such, the Chachiyo formula used in phonon dispersion calculation has proven to be valid and therefore extends the use of LDA from relying on fitting to the first-principles correlation functional that provides a higher predictive power.