We present several new sets of grids of model stellar atmospheres computed with modified versions of the ATLAS9 code. The individual sets differ essentially in the physics used for the treatment of the convective energy transport and in the number of layers used to describe the vertical structure of the atmospheres. These grids of model atmospheres provide a basis for the characterization of the COROT seismology targets, in particular the precise and reliable determination of their effective temperatures, surface gravities and abundances.