Size dependence of the Raman spectra in an amorphous-nanocrystalline mixedphase: the glacial state of triphenyl phosphite

Raman scattering investigations on triphenyl phosphite, performed in both t he low- and high-wavenumber ranges, provide a detailed description of the g lacial state. The latter can be described as a two-phase (amorphous-nanocry stalline) system if it is prepared by isothermal aging in the 210-222 K tem perature range. From two different procedures the nanocrystalline volume fr action can be determined in glacial states prepared in the above temperatur e range. The Raman spectra in the range 840-1640 cm(-1) reveals that T-a = 224 K is a critical temperature from which the supercooled liquid isotherma lly transforms into a microstructure rather than nanocrystallized domains. In this case the volume of the non-transformed supercooled liquid remaining in the intergranular space was estimated with respect to the volume of cry stallized matter. Copyright (C) 2001 John Wiley & Sons, Ltd.