Dissolution dynamics of NaCl nanocrystal in liquid water.

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 Cl(-) ion at a corner site, followed by a Na(+) ion nearby. Both show directional preference in the dissolution path. An ion sequence with alternating charge, i.e., Cl(-), Na(+), Cl(-), 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.