Tin-pest problem as a test of density functionals using high-throughput calculations

At ambient pressure tin transforms from its ground state, the semimetal $\ensuremath{\alpha}$-Sn (diamond structure), to metallic $\ensuremath{\beta}$-Sn at $13{\phantom{\rule{0.16em}{0ex}}}^{\ensuremath{\circ}}\mathrm{C}$ (286 K). There may be a further transition simple hexagonal phase, $\ensuremath{\gamma}$-Sn, above 450 K. These relatively low temperatures are due small energy differences between structures, $\ensuremath{\approx}20$ meV/atom $\ensuremath{\alpha}$- and $\ensuremath{\beta}$-Sn, which makes an exceptionally sensitive test of accuracy density functionals computational methods used in calculating electronic vibrational energy, including zero-point energy. Here we use high-throughput automatic-flow (AFLOW) method study energetics multiple structures using variety examine contributions free with AFLOW Automatic Phonon Library (APL). We look successes deficiencies each functional. also discuss necessity testing calculations for convergence systems differences.