Lattice constant measurements on the 106 K transition of SrTiO₃

Abstract

Abstract The temperature dependence of the lattice constant of SrTiO3, in particular around the 106 K transition, has been measured by using a double-crystal X-ray diffraction method; a relative accuracy of 10−5 is attained. The results are compared with those of EPR in terms of static rotation ø of TiO6 octahedra around [001]. The transition is characterized by two temperature regions below Ta : Above 75 K an increase of rotation ø completely matches a contraction of the lattice constant a, while below 75 K ø does not match a.