  1LO optical phonons in free-standing mixed Cd1-xZnxS nanocrystals,
synthesized using chemical precipitation, are investigated using Raman
spectroscopy. As expected for the nanocrystals, the 1-LO modes are found to
appear at slightly lower wavenumbers than those in the bulk mixed crystals and
exhibit one mode behavior. On the other hand, the line broadening is found to
be much more than that can be accounted on the basis of phonon confinement.
  From the detailed line shape analysis it turns out that the substitutional
disorder in the mixed crystals contributes much more to the line broadening
than the phonon confinement. The linewidth arising from these mechanisms are
also extracted from the analysis.
