Abstrakt: |
Analysis of the peak position and the linewidths of various infrared modes is performed at high (300-850 K) and low (1.5-300 K) temperatures using the experimental data from the literature for LiKSO4 which exhibits a sequence of phase transitions. The temperature dependences of the frequency and the linewidth which are derived from the anharmonic self-energy are fitted to the observed peak positions and the linewidths of the S-O stretching modes (internal modes at 1135 cm and at 1180 cm), peak position of the S-O bending (internal) modes, the peak position and the linewidth of the Li mode at 429 cm (external mode), and of the infrared band at 363 cm for LiKSO4. Our calculated peak positions and the linewidths, which are in good agreement with the observed data show that the anharmonic self-energy model describes adequately the observed behavior of the successive phase transitions in LiKSO4. [ABSTRACT FROM AUTHOR] |