[en] The authors study the sup(95m)Tc decay in a K₂sup(99(95m))TcF₆ solid matrix and in solutions and compare the results with those obtained on K₂sup(99(95m))TcCl₆. (Auth.)

[en] Although the distribution of sup(95g)Tc amongst the different products following isomeric transition in solid samples of pertechnetates is independent of the pH of the solution in which the dissolution for analysis takes place, the same is not true if the decay takes place in solution. The sup(95g)Tc appears in neutral and cationic forms as well as TcO^-₄ and another anionic species. Introduction of scavengers into the solution suggests that this pH effect may arise from reactions of the primary sup(95g)Tc products with radiolytic products formed in the solution by Auger electrons released during the isomeric transition. (orig.)

[en] The chemical effects of the I.T. of sup(95m)Tc have been studied in M₂TcF₆ in the solid matrix and in solutions. The retention of sup(95g)Tc for the solid matrix was found to be about 90%. The unretained sup(95g)Tc appears as TcF₅(H₂O)^-, neutral and TcO₄^- species. At low concentration (10^-3-10^-2 M) of K₂TcF₆ in HF, H₂SO₄ and H₂O solutions the retention was found to be about 1%. The unretained sup(95g)Tc was found preponderately as TcF₅(H₂O)^-: 90% in HF, 80% in H₂O and 50% in H₂SO₄. An effect of temperature on the unretained sup(95g)Tc distribution in sulfuric acid was observed. At higher concentration of K₂TcF₆ in solution, the retention increases at the expense of TcF₅(H₂O)^- and uncharged species. A comparison with previously obtained results on the K₂TcCl₆ is made. (orig.)

[en] The chemical effects of the isomeric transition of ⁹⁵sup(m)Tc have been investigated in potassium and ammonium hexachloro-technetate(IV) in solution and solid matrix. The retention of ⁹⁵sup(g)Tc in sulphuric solution was found to be close to zero. Change of the acid concentration had no effect. Nor was 3 M HCl solution much different. The retentions for the solid matrices were found to be higher than 70%. The unretained ⁹⁵sup(g)Tc appeared as cationic, hydrated TcO₂, [TcCl₅(H₂O)]^- and TcO^-₄ species. The last species only amounted to about 1%. (orig.)

[en] The chemical effects of the isomeric transition of sup(95m)Tc have been extended to potassium and ammonium hexachloro-technetate (IV) solution and solid matrix. (Auth.)

[en] The chemical effects of isomeric transition of ⁹⁵sup(m)Tc have been investigated in solid lithium, potassium and ammonium pertechnetate matrices. The retention of ⁹⁵gTc in NH₄⁹⁹sup(()⁹⁵sup(m)sup())TcO₄ was about 60% and in Li⁹⁹sup(()⁹⁵sup(m)sup())TcO₄ and K⁹⁹sup(()⁹⁵sup(m)sup())TcO₄ higher than 70%. The unretained ⁹⁵gTc was found preponderantly as a cationic and an uncharged species. Under corresponding storage conditions the retentions for Li TcO₄ were higher than for KTcO₄. The influence of temperature and ambient atmosphere was studied. The samples stored in vacuum showed a higher retention than those kept in air. Thermal annealing leads to an increase in retention. (orig.)