Light scattering study of boron nitride microcrystals

摘要: Raman scattering and x-ray diffraction measurements are used to correlate finite-size effects on the spectra of nonpolar vibrational modes in BN. The BN microcrystalline samples exhibited domain sizes varying from 4.4 78.5 nm plane 1.5 47.5 perpendicular planes. indicated that high-frequency ${E}_{2g}$ mode shifted higher frequency broadened as crystallite size decreased. A formulation cross section for microcrystals is presented. development includes evaluation susceptibility correlation function over a limited spatial extent. results indicate spectral changes related phonon dispersion, wave-vector uncertainty accounted for. applied describe light results, good agreement was obtained observed shift frequency.