First-principles prediction of ferroelastic phase transition in AlPO4

摘要: Abstract First-principles calculations on AlPO4 predicted the stability of a stishovite-like phase and existence ferroelastic transition between this m-CaCl2 phase. The is consistently supported from point view energy, spontaneous strain, tilt angles octahedra, behaviour soft-modes. soft modes are B 1 g in Ag static occurs at pressure 45.3 GPa, which was judged character modes, fields were investigated up to high temperatures. For computational methods, study calculated total energies with density functional theory (DFT), phonon properties perturbation (DFPT), high-pressure high-temperature boundaries within quasiharmonic approximation (QHA).