Numerical simulations examining chemical interactions of water molecules with forsterite grains have demonstrated the efficacy of nebular gas adsorption as a viable mechanism for water delivery to the terrestrial planets. Nevertheless, a comprehensive picture detailing the water-adsorption mechanisms on forsterite is not yet available. Towards this end, using accurate first-principles density functional theory, we examine the adsorption mechanisms of water on the (001), (100), (010) and (110) surfaces of forsterite. While dissociative adsorption is found to be the most energetically favourable process, two stable associative adsorption configurations are also identified. In dual-site adsorption, the water molecule interacts strongly with surface magnesium and oxygen atoms, whereas single-site adsorption occurs only through the interaction with a surface Mg atom. This results in dual-site adsorption being more stable than single-site adsorption.
|Original language||English (US)|
|Journal||Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences|
|Publication status||Published - Jul 13 2013|
- Density functional theory
- Endogenous water
ASJC Scopus subject areas
- Physics and Astronomy(all)