The intensity of scattering I(θ) by transparent and absorbing spheres has been calculated from exact Mie theory for values of radius from 0.1 µm to 100 ,µm, wavelength 5461 Å, and the following values of refractive index m - im′: (1) m = 1.01, 1.05, 1.1 (0.1) 2.0, m′ = 0; (2) m = 2, m′ = 0.002, 0.02, 0.2, and 2. The calculations have been made for a range of scattering angle θ large enough to indicate the first maximum in I(θ)θ2. According to the Sloan method for determining particle radius, the location of this maximum is inversely proportional to radius, independent of refractive index. The exact calculations show that this is accurate for radii above 10 µm, but for smaller particles the value of the refractive index affects the location to some extent.
E. J. Meehan and A. E. Gyberg, "Particle-Size Determination by Low-Angle Light Scattering: Effect of Refractive Index," Appl. Opt. 12, 551-554 (1973)