The dissolution dynamics of a NaCl nanocrystal in liquid water was studied using molecular dynamics simulations. The dissolution process was found to start with a ${\mathrm{Cl}}^{-}$ ion at a corner site, followed by a ${\mathrm{Na}}^{+}$ ion nearby. Both show directional preference in the dissolution path. An ion sequence with alternating charge, i.e., ${\mathrm{Cl}}^{-},{\mathrm{Na}}^{+},{\mathrm{Cl}}^{-},{\mathrm{Na}}^{+}$, etc. was found to dominate the dissolution process. This image can be understood from the ionic hydration structures and the Coulomb interaction between the ions.

• Received 28 February 2005

DOI:https://doi.org/10.1103/PhysRevE.72.012602