Correlation between surface rumpling and structural phase transformation   of SrTiO3
  We present x-ray reflectivity, x-ray diffraction and atomic force microscopy measurements of single crystal SrTiO3 taken as a function of temperature. We found a rumpling transformation of the SrTiO3 surface after cooling the sample below ~105 K. The rumpling transformation is correlated with the cubic to tetragonal phase transformation that occurs at the same temperature. The rumpling transformation is reversible. 
S. Singh, Te-Yu Chien, J. R. Guest and M. R. Fitzsimmons
cond-mat.mtrl-sci cond-mat.other