Photochemical aerosol formation of haloidbenzenes—Comparison between theory and experiment

Experimental data of haloidbenzene (PhHal) photonucleation by Dubtsov et al. (1992 J. Aerosol Sci. 23, 181) are reevaluated using improved computer simulations of number concentration and size distribution during photonucleation based on solving the Smoluchowski coagulation equations. A new two-step algorithm for their solution was used. A new approach to determine monomer formation rate and a minimal detectable cluster size is proposed. Measured number concentrations vs irradiation time and size distributions (2–100 nm) are in reasonable agreement with the model results. The experimentally observed bimodal particle size distribution with irradiation time-dependent concentration ratio between modes is reproduced in the model. The model also qualitatively correctly describes the temporal evolution of the size distribution. Remaining quantitative discrepancies are discussed.