Determination of Ground State Structures of Snx− (x=21–35) Clusters

Abstract

AbstractIn this work, an unbiased global search with a homemade genetic algorithm was performed to investigate the structural evolution and electronic properties of Snx− (x=21–35) clusters with density functional theory (DFT) calculations. All the ground‐state structures for all these Snx− (x=21–35) clusters have been confirmed by the comparison of the experimental and simulated photoelectron spectra (PESs). It has been revealed that all Snx− (x=21–35) clusters are tricapped trigonal prism (TTP)‐based structures consisting of two (for sizes x=21–28) or three (for x=29–35) TTP units, with the remaining atoms adsorbed on the surface or inserted between TTP units. The gradually decreasing HOMO‐LUMO gaps indicate that these clusters are undergoing semiconductor‐to‐metal transformation. The average binding energies show that the structural stabilities of Snx− clusters are not as good as that of silicon and germanium clusters. It found that sizes x=23, 25, 29, 33 show high relative stability.