Prediction of a bcc–hcp phase transition for Sn: A first-principles study

The high-pressure structural transformation of elemental Sn is studied using an ab initio density functional theory implementation of the metadynamics method that predicts with sufficient compression, Sn will transform from the bcc structure into an hcp structure. The low-free-energy pathway associated with this phase transition is characterized as the Burgers transition mechanism. The superconducting properties of Sn under pressure are also investigated. Both bcc and hcp structures of Sn exhibit very weak electron–phonon coupling and therefore would not sustain superconductivity at high pressure.

► We study the high-pressure structural transformation of Sn using the metadynamics method.
► We predict that with sufficient compression Sn will transform from the bcc structure into an hcp structure.
► We characterize the low-free-energy pathway associated with this phase transition.
► We predict that superconductivity of Sn is suppressed at high pressure.