The knowledge of the structural changes that occur during the lithographic process using chemically amplified resists (CARs) is of great importance in process and resist optimization. Molecular dynamics (MD) is a suitable method for the simulation of these microscopic changes. A detailed description of the lithographic procedure including reaction propagation, acid diffusion, cage effects, free volume effects and developer selectivity can be included in such a model. The comparison of contrast curve data and acid diffusion measurements with MD modeling, leading to the evaluation of microscopic parameters are presented in this paper.