Solid State Concepts in Radiation Chemistry and Biology
The processes taking place between the initial deposition of ionizing energy and the chemical utilization of it in radiation chemistry and radiation biology are discussed from a solid state point of view. This realm, often referred to as the physicochemical realm of radiation chemistry, occurs in the time range 10-16 < t < 10-13 sec, and its understanding is of paramount importance in the interpretation and prediction of channels for energy dissipation in radiation chemistry and biology. A recently discovered exciton fission process is suggested as the important electronic relaxation mechanism in the physicochemical realm. The better known events of “internal conversion” and “intersystem crossing” follow the higher energy relaxation mechanisms and help to localize the excitations in low-lying neutral or ionic states of the aggregate so that chemistry can eventually occur.
KeywordsPrimary Electron Excited Electron Radiation Chemistry Positive Hole Frenkel Exciton
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