The distributions of energy deposition events for electrons in gaseous and liquid water and in amorphous ice have been calculated. These calculations make use of an inelastic cross section that takes into account binding energy, exchange, and relativistic effects and that is based on experimentally determined dipole oscillator strength distributions. The most probable energy loss in a single event by a 1-MeV electron is 22.5 eV in the condensed phases and 13.5 eV in the gaseous phase, while the average energy loss is 34, 38, and 40 eV/event for gaseous and liquid water and amorphous ice, respectively. Very little dependence of the distributions on incident electron energy is found. At 1 MeV the differential or single event distribution is found to be the same as the integral or cumulative distribution. The fractions of the total energy lost in events that are less than 100 eV are 0.76, 0.75, and 0.69 for gaseous and liquid water and amorphous ice, respectively. © 1990 American Chemical Society.
