[en] The ingredients and the results of our Monte Carlo simulation of the slowing down of nonrelativistic electrons in irradiated liquid water and of the evolution of the created species are presented. The proportion of excited and ionized species can be seen in the calculated yields at 10^-15 s. A fast reorganization of the medium allows radicals and molecular products to be formed and their yields at 10^-12 are calculated. Yields of 5.3 electrons and 6.0 hydroxyl radicals per 100 eV absorbed energy are compatible with experimental values at 30 and 200 picoseconds