Theoretical isothermal equation of state of the high-pressure phases of silicon.

Abstract

The 0-K isotherms of the high-pressure hexagonal-close-packed and face-centered-cubic structures of silicon are computed using a linear muffin-tin orbital electron-band theory technique. Our theoretical pressure-volume data are fitted to the universal equation of state by least-squares procedures and the zero-pressure bulk modulus ${\mathrm{B}}_{0}$, its first pressure derivative ${\mathrm{B}}_{0}^{\ensuremath{'}}$, and the zero-pressure volume ${\mathrm{V}}_{\mathrm{n}}$ are obtained. Our results are compared with the recent experimental and some earlier theoretical results.