A density functional study on the aggregation of alumina clusters

A calculation has been performed to explore the mechanism of aggregation reaction between two small molecular clusters [(Al2O3)n1 and (Al2O3)n2] by the density functional theory method. Five pathways of aggregation reactions between two different (Al2O3)1 clusters isomers were identified. The detailed process of (Al2O3)1 interaction with (Al2O3)2 were also obtained. All the products of the aggregation reactions between two cage structures are cage-dimer structures. We calculated the thermodynamic properties of all the aggregate clusters. The Gibbs free energy changes of aggregation reactions in 0–1000 K were negative and increased with the temperature increase. The energy changes of enthalpy and entropy were also obtained.