Theoretical prediction of ring structures for ZnS quantum dots

The lowest energy structure of ZnS quantum dots of different sizes have been determined by using a search based on genetic algorithm (GA) coupled with the density-functional tight-binding method (DFTB). The GA search converges to a rather new ring-like configurations of ZnS quantum dots. These ring-like clusters have higher HOMO–LUMO gap values compared to other known structures (such as hollow, zinc-blende and wurtzite) of ZnS QDs.