Datensatz

Zusammenfassung

The growth of NaCl and CaF2 aggregates is studied with the framework of an atomistic simulation approach. Our method combines a Monte-Carlo type scheme for the identification of ion adsorption sites and structural optimization of the ion cluster after individual growth steps. This allows investigating putative conformers of ion aggregates as a function of size. The structure of clusters counting only a small number of ions was found to be quite amorphous. During the early stage of aggregate growth, the addition of further ions leads to considerable structural changes. Once the clusters exceed a critical size, a disorder[RIGHTWARDS ARROW]order transition is observed, leading to large domains exhibiting motifs of the crystalline structure. Such crystalline regions were found to be stable and hence change only marginally during further aggregate growth.