Influence of size effects on para-dichlorobenzene lattice dynamics

We have obtained experimental low-frequency Raman spectra for light scattering by nanoparticles of para-dichlorobenzene of size ∼300-70 nm. As their sizes decrease, the line frequencies decrease. The size of the nanoparticles was determined using an electron microscope. We found that in the lattice vibrational spectrum of nanoparticles of size 300-70 nm, a summed spectrum appears from α-para-dichlorobenzene and β-para-ichlorobenzene. This is consistent with molecular dynamics calculations of the structure of the nanoparticle and calculations of the histograms for the lattice vibrational spectra by the Dean method. (authors)