[en] The solid-state reactions occurring during the moderation of (n, γ) produced hot ⁸²Br have been studied in K₂OsBr₆-K₂OsCl₆ mixed crystals. The main products are Os⁸²BrBr2/5^-, Os⁸²BrCl2/5^-, and ⁸²Br^-, but even the more extensively mixed species Os⁸²BrBr₄Cl^2- and Os⁸²BrBrCl2/4^- are obtained in significant amounts. The most important reaction found is the replacement process (billiard-ball process). In some cases the recoil atoms interact with more than one ligand and intermediate ligand vacancy complex anions Os⁸²BrBr_n□2/5^-_-n and Os⁸²BrCl_n□2/5^-_-n (n=0-5) are formed. The vacancies are assumed to be filled by mobile halides from the lattice. From the fractions of Os⁸²BrBr_nCl2/5^-_-n (n=0-5) and ⁸²Br^- and their dependence on the mixed crystal composition the following results were obtained with the help of the program PRIMULA; 5-15% interstitirals, 5-6% primary retention, 51-65% replacement, 11-19% replacement plus one additional vacancy, 6-10% replacement plus two or more additional vacancies. A small reactor effect is accounted for by different neutron energy spectra. (orig.)