Structural phase boundary of SrTiO₃ under [111] stress

The first electron paramagnetic-resonance (EPR) experiments under tension in an oxide are reported. They show that for SrTiO3 in the physically accessible region, the cubictetragonal phase boundary is along the [111] tension axis and not temperature near the particular novel multicritical point, which occurs for finite stress. This occurrence is tentatively attributed to the cubic anisotropic fluctuations in this material. © 1982 Springer-Verlag.