Chemical Effects of Nuclear Transformations in Mixed Crystals 8. Thermal Annealing of ¹⁸⁶Re in Neutron Irradiated K₂ReBr₆-K₂SnCl₆ Mixed Crystals. I

Abstract

In Κ, ReBr 6 -K 2 SnCl 6 mixed crystals the nuclear process " 5 Re (n, y) 1,6 Re produces according to the chemical analysis all species 1 " ReBr"Cl^" (n = 0 ... 6) and (from excited or interstitial 1,6 Re recoils) 1 " ReO;. Upon thermal annealing 1 " ReO; decreases and the fractions of all " 6 ReBr"CljI" species increase. Approximately one third of the annealing occurs at 50°C producing merely 1 " ReBrJ ~ which is strong evidence for a proper recombination of 1 " Re with its six originally coordinated Br ligands. The remaining annealing proceeds with increasing temperature and is due to the reaction of 1 " Re recoil atoms with halides, both CI and Br, from the lattice. As there is no preference for a special species no conclusions can be drawn concerning the lattice site where these reacting '"Re recoils come to rest.