Theoretical Study on Multiple Exciton Generation of Si 6 X ( X =Cu, Ag and Au) Clusters

Multiple exciton generation (MEG) of Si 6 X ( X =Cu, Ag and Au) clusters is investigated by using symmetry adapted cluster theory with configuration interaction and pseudo potential LANL2DZ basis set. Before MEG calculations, geometrical structures of clusters are optimized and their energy stabilities are confirmed by frequency analysis based on density functional theory method and all-electron double zeta valence quality plus polarization functions primary basis sets DZP-DKH. It indicates that double exciton is found dominating component and MEG of clusters appear in visible range although the strong part is in ultraviolet light range, which provides information for potential materials utilizing MEG to harvest energy of solar light.