Raman and fluorescent scattering by molecules embedded in small particles: numerical results for incoherent optical processes

When molecules which give rise to Raman and fluorescent light scattering are distributed within small dielectric particles, the signal is affected by the morphology and optical properties of the particle, and the distribution of molecules of interest within it. These effects are manifested by changes in the magnitude, in the angular distribution, and in the polarization of the scattered radiation. Furthermore, because the effects vary with the wavelengths of both the exciting and the emitted radiation, the emission spectrum for fluorescence may vary with the exciting wavelength, the morphology and optical properties of the particle, the distribution of the active molecules within the particle, and even the angle of observation. These phenomena must be considered in quantitative procedures for utilizing Raman and fluorescent scattering for determining the concentration of specific molecules in small particles such as aerosols or biological cells. The effects are illustrated here by a series of numerical calculations involving inelastic noncoherent scattering by molecules variously embedded in dielectric spheres.