FORMATION OF EXCITONS IN LIQUID WATER DURING IRRADIATION

The optical absorption spectrum of liquid water was analyzed. Within t he framework of the semiconductor model, it was shown that irradiation of liquid water leads to formation of excitons of energy 5.76 eV. The spectrum of exciton energies was calculated. The dynamics of exciton relaxation was studied. The water ionization energy was estimated from the optical absorption spectrum to be 9.2 eV. Ionization of water und er UV laser irradiation was considered in terms of exciton-exciton cou pling, which reduces the effective ionization energy to 6.5 eV. The me chanism of radiolysis of dilute aqueous solutions was discussed. The c alculations showed that more than 70% of absorbed energy is delocalize d because of generation of excitons and plasmons in water.