Interpretation of radiation damage in platinum

The paper analyzes the resistivity-versus-dose curves (damage curves) measured on platinum during light-ion or electron irradiation at various temperatures. The analysis is based on a generalization of Walker's unsaturable trap model that allows for the possibility of the existence of two distinct configurations of self-interstitials. The available data indicate clearly that in addition to the Stage Isub(E) interstitial a second self-interstitial configuration exists, which begins to migrate freely at about 300 K. This result decides the controversy between Jackson on the one hand and van den Beukel and Schilling on the other hand on the labelling of recovery stages in platinum in favour of the former (i.e. the 300 K recovery should be named Stage III). Platinum belongs to the group of metals in which th existence of two self-interstitial configurations is established. The temperature of thermal conversion from the metastable (Isub(E)) to the stable (III) configuration is found to lie above 140 K. (author)