High-pressure behaviour of KMF₃perovskites

Abstract

The structural stability of cubic KMF3 (M: Mg, Zn, Co, Ni) perovskites has been studied by powder X-ray diffraction under pressure. Neither superlattice reflections nor peak splitting associated to a phase transition were detected in the 0–10 GPa pressure range. Furthermore, KMgF3 showed no structural changes up to 50 GPa. The results were compared with previous reports on isostructural KMnF3. Tolerance factor and site parameters ratio have been analysed as high-pressure stability indexes for this family of perovskites.