Abstract
First principles calculations have been made to theoretically interpret the structural stability of SrTiO3 as a function of pressure or strain. We show that the orthorhombic Pbnm structure is more stable than the ideal perovskite one due to rotations of TiO6 octahedrons at high pressures or deformations of TiO6 octahedrons at low pressures. Such a study is extended to the structural stability of the Ruddlesden–Popper Sr n +1Ti n O3 n +1 phases for n = 1, 2 and 3, in which the lattice constraints are induced by the intercalation of SrO layers in the perovskite structure.
Acknowledgments
We acknowledge Laboratoire de Physique et Modélisation des Milieux Condensés for computational resources on the PC cluster PHYNUM (CIMENT, Grenoble).