A new semi-empirical model for the oxidation of PAHs physisorbed on soot. I. Application to the reaction C6H6 + OH.

Sylvain Picaud (1) , Gyorgy Hantal (1, 2) , Barbara Collignon (1) , Paul N.M. Hoang (1) , Jean-Claude Rayez (3) , Marie-Thérèse Rayez (3)

1 UFC - Université de Franche-Comté
2 Laboratory of Interfaces and Nanosized Systems, Institute of Chemistry
3 UB - Université Sciences et Technologies - Bordeaux 1

In the present paper, we have used a new semi-empirical method to characterize the oxidation by OH of a benzene molecule adsorbed on a soot surface modelled by a graphene-like cluster. This method is based on an electrostatic and induction contribution calculated at the SCF AM1 level associated with a sum of two-body dispersion terms of the C6/R6 form. This so-called AM1-D method has been used to compare the characteristics of the oxidation reaction for the adsorbed benzene with those of the corresponding reaction in the gas phase. The main conclusion of the present work is a clear inhibition of the oxidation process by the adsorption of the benzene molecule on the soot surface. This conclusion is in qualitative agreement with experimental observations, concerning however larger PAH molecules.

Mots clés: Physical Sciences

Sylvain Picaud, Gyorgy Hantal, Barbara Collignon, Paul N.M. Hoang, Jean-Claude Rayez, et al.. A new semi-empirical model for the oxidation of PAHs physisorbed on soot. I. Application to the reaction C6H6 + OH.. Molecular Simulation, 2009, 35 (12-13), pp.1130-1139. ⟨10.1080/08927020902874016⟩. ⟨hal-00530450⟩