First-principles pseudopotential study of the structural phases of silicon

摘要: A first-principles pseudopotential study of 11 phases silicon is reported: diamond (cd), body-centered cubic (bcc), face-centered (fcc), tetragonal (bct), simple hexagonal (sh), hexagonal-close-packed (hcp), double-hexagonal-close-packed (dhcp), (sc), \ensuremath{\beta}-tin, a structure with eight atoms per unit cell (bc8), and 12 (st12). For each for volume considered we have minimized the energy respect to all structural degrees freedom. We used large basis sets very careful integrations over Brillouin zone resolve small differences between structures, our pseudopotentials incorporate nonlinear core exchange-correlation corrections, leading more accurate results than those previous calculations. find good agreement experiments some calculations but few discrepancies remain gain insights into high-pressure phase diagram silicon.