Ab initio calculation of the properties and pressure induced transition of Sn

In this paper, ab initio calculations of the electronic structure and pressure induced phase transition are performed for Sn by the density functional theory, both local density approximation (LDA) and generalized gradient approximation (GGA) are chosen for the calculation of exchange–correlation potential. Good agreement with previous experiments and calculations is found for the ground state properties of each phase at atmospheric pressure. Both the band structure and density of states (DOS) of β - Sn are calculated and found to change greatly with the pressure. The transition sequence of α - Sn → β - Sn → bct (body-centered tetragonal) → bcc (body-centered cubic) → hcp (hexagonal close-packed) phase is obtained within generalized gradient approximation, and the conclusion is consistent with experiment. The transition pressures and atom volumes of Sn are also calculated within generalized gradient approximation (GGA). The results show that the transition of α - Sn to β - Sn is at 0.7 GPa, β - Sn to bct is at 12 GPa, and bct to bcc is at 45 GPa, bcc to hcp is at 160 GPa. These results are much closer to the experimental data than those calculated within local density approximation (LDA).