Temperature-dependent Raman study of taurine single crystal

Polarized Raman spectra of an oriented taurine single crystal were studied at temperatures ranging from 7 to 300 K. The results show that several band s present a linewidth increase characteristic of anharmonic effects, and th at the band related to the CSH torsional mode splits at low temperatures. A n abrupt wavenumber jump of an external mode was associated with a phase tr ansition undergone by the crystal between 250 and 260 K on cooling. A calor imetric investigation over the temperature range 173-308 K confirmed the ex istence of a first-order phase transition (at 251 K, on cooling), with a te mperature hysteresis of 21 K. Copyright (C) 2001 John Wiley & Sons, Ltd.