Technetium(VII) oxide is the chemical compound with the formula Tc2O7. This yellow volatile solid is a rare example of a molecular binary metal oxide, the other examples being RuO4, OsO4, and the unstable Mn2O7. It adopts a centrosymmetric corner-shared bi-tetrahedral structure in which the terminal and bridging Tc-O bonds are 167pm and 184 pm respectively and the Tc-O-Tc angle is 180°.[1]
Technetium(VII) oxide is prepared by the oxidation of technetium at 450–500 °C:[2]
4 Tc + 7 O2 → 2 Tc2O7It is the anhydride of pertechnetic acid and the precursor to sodium pertechnetate:
Tc2O7 + 2 H2O → 2 HTcO4
Tc2O7 + 2 NaOH → 2 NaTcO4 + H2O