RAMAN-SCATTERING STUDY OF PHASE TRANSITION IN LIKSO4 AT LOW TEMPERATURE.

Bansal et al. have reported that the LiKSO//4 crystal undergoes a subtle structural phase transition on 201K while being cooled according to the temperature dependence of Raman spectrum intensity for some polar phonon modes. They found the low temperature phase to be C//3//v**4. But their evidences were not sufficient. In the present work we report further refined Raman spectra in LiKSO//4 at the both 210K and 203K. After carefully analyzing their variations and considering the correlation of space group symmetry, we found that the pattern of the pattern of the structural phase transition in LiKSO//4 at 203K is C//6**6 yields C//3//v**4, while being cooled, seems to be associated with a rearrangment of two adjacent SO//4 tetrahedra in the unit cell.