Conversion of Al13 Keggin ε into Al30: a reaction controlled by aluminum monomers

In situ 27Al NMR experiments under hydrothermal and room temperature conditions demonstrate that aluminum monomers are the species controlling the Al13 Keggin ε conversion into Al30. New 27Al NMR signatures of Keggin-type aluminum polycation are observed in solution. A chemical pathway is proposed to explain the isomerization process.