A coarse-grained representation of material can significantly speed up molecular dynamics simulations. The difficulty arises when the simulations need to include chemical reactions. We have developed a methodology for including the effects of chemical reactions in coarse-grained molecular dynamics simulations, namely the Coarse-Grained Chemical Reactions Model (CGCRM). The model adopts physically and experimentally based parameters of a specific material, such as photochemical passways, the probabilities, and the exothermicities of chemical reactions. We have applied this approach to elucidate the effects of photochemical reactions on laser ablation of organic and polymeric materials. We find that the model provides a plausible description of the essential processes. (C) 2007 Elsevier B.V. All rights reserved.