Two RhIII-substituted polyoxoniobates and their base-induced transformation: [H2RhNb9O28]6− and [Rh2(OH)4Nb10O30]8−†
Abstract
Two new rhodium-substituted polyoxoniobates, [H2RhNb9O28]6− (RhNb9) and [Rh2(OH)4Nb10O30]8− (Rh2Nb10) are reported. The two distinct RhIII-substituted niobate clusters behave differently when the pH is raised with TMAOH: the Rh2Nb10 is stable until pH ∼ 12.7, but RhNb9 dissociates to form RhNb5 and RhNb10, similar to some of our other metal-substituted niobates, such as the MNb9 ions (M = Cr or Mn), which transform to MNb10 when the solution pH is raised.