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Facile Preparation of Ultrafine Aluminum Hydroxide Particles with or without Mesoporous MCM-41 in Ambient Environments
Published on: May 11, 2017
The energetics of isomerisation in Keggin-series aluminate cations
C André Ohlin1, James R Rustad, William H Casey
1School of Chemistry, Monash University, Melbourne, Australia. andy.ohlin@monash.edu.
Abstract:
Electronic-structure calculations show that the ε-isomer of the polyoxoaluminate ion in the Keggin structure [AlO4-(Al(OH)2(H2O))12](7+) is the thermodynamically favoured one. Direct interconversion between the ε- and δ-isomers via cap rotation has a prohibitively high energy barrier in vacuo, suggesting that isomerisation in solution either proceeds via a dissolution-precipitation pathway, or that solvation and/or coordination to counterions reduces the barrier significantly. The implications for the formation of the [Al2O8Al28(OH)56(H2O)26](18+) ion are discussed.
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