The results of an experimental study of the optical characteristics and microstructure of the dispersed phase of the products of combustion of organic fuel in oxygen and atmospheric air are analyzed. For gaseous fuels CmHn, the concentration of soot sol increases with an increase in the ratio of elements Cm / Hn. The microstructure of soot sol strongly depends on the residence time of the combustion products in the flame zone (chemical reaction zone) and the thermodynamic temperature. The maximum ash content is observed at thermodynamic temperatures of 1500-1800K zone of chemical reactions. The minimum ash content is observed when burning fossil fuels in oxygen with a value of the coefficient of excess oxygen α = 1,03. A technique is proposed for measuring the microstructure of soot sol in atmospheric emissions of the combustion products of turbojet engines, vehicles, and power plants. The results of studies of the microstructure of the dispersed phase of fuel combustion products are used to calculate the light scattering matrices of carbon black sol according to the Mi theory. The radiation characteristics of soot sols are simulated by their superposition for different fractions i of the sol microstructure with normalization to optical density |τi| and a wavelength of λ = 0.55mkm. The optical densities |τi| for λ=0,55mkm for components i are given in numerical form depending on the height z in the combustion chamber. The radiation characteristics (absorption, scattering cross section and scattering indicatrix) are presented in the spectral region of 0.2–40mkm in the form of an electronic computer database for various gamma distributions of the carbon structure of soot sol.