I studied the optical properties of thin layers of nigrosine on glass. I was mainly interested in their complex refractive index, which I measured with optical ellipsometry. Using the Lorentz model and the assumption that the material is a dielectric, I described the real and imaginary part of the dielectric function of nigrosine. Aerosolized nigrosine forms spherical particles whose sizes and shapes were analyzed by scanning electron microscopy. For this purpose, I used a filter on which nigrosine particles were sprayed. Their scattering properties can be described by the scattering theory for homogeneous spherical particles in air. The calculated scattering coefficient is important in determining the absorption coefficient of an aerosol at a given wavelength, since during measurements we usually analyze extinction and not just absorption.
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