Raman spectroscopy of CdS nanoparticles

CdS nanoparticles with average radius R_o = 2.2 nm have been investigated by Raman scattering measurements. The nanoparticles, synthesized using aqueous solution precipitation, are small enough to show effects due to confinement. In the Raman spectra of CdS nanoparticles an asymmetric Raman line was observed. The dominant line was at about 300 cm^–1 having asymmetric broadening for ω < 300 cm^–1. We considered a single crystalline sphere to calculate the relative contributions of the confined modes to the Raman scattering. The second harmonic of these confined modes was also registered. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)