2002 年 51 巻 2 号 p. 65-71
The first-order Raman spectra of CdWO4 crystal are measured at room temperature. The phonon disper-sion curves of CdWO4 are calculated on the basis of a rigid-ion model using the measured frequency values. The first-order Raman spectra of external Ag mode (310cm-1 and 550cm-1) in the CdWO4 crystal have been measured in the temperature range between 77 and 473K. The temperature dependence for the linewidth of the external Ag modes has been analyzed at 310cm-1 and 550cm-1 using the lattice dynamical perturebative treatment, and the calculated result agrees with the observed one in the temperature range of 77-473K. Thus, the temperature dependence of linewidth of the external Ag modes in CdWO4 crystal is ap-proximately explained by the cubic anharmonic term in the expansion series of the crystal potential energy.
