Calculation of water-exchange rates on aqueous polynuclear clusters and at oxide-water interfaces
The rates of a wide variety of reactions in aqueous coordination compounds can be correlated with lifetimes of water molecules in the inner-coordination shell of the metal. For simple octahedral metal ions, these lifetimes span ∼1020 but are unknown, and experimentally inaccessible, for reactive sites in interfacial environments. Using recent data on nanometer-sized aqueous aluminum clusters, we show that lifetimes can be calculated from reactive-flux molecular dynamics simulations. Rates scale with the calculated metal-water bond lengths. Surprisingly, on all aluminum(III) mineral surface sites investigated, waters have lifetimes in the range of 10-8- 10-10 s, making the surface sites as fast as the most reactive ions in the solution. © 2007 American Chemical Society.
Publication Source (Journal or Book title)
Wang, J., Rustad, J., & Casey, W. (2007). Calculation of water-exchange rates on aqueous polynuclear clusters and at oxide-water interfaces. Inorganic Chemistry, 46 (8), 2962-2964. https://doi.org/10.1021/ic070079+