Structure And Stability Of Al_mS_n/Al_mS_n~±clusters

Recently the study of doped clusters has become a hotspot. Especially the theoretical and experimental research of aluminum-sulfur doped clusters has always been paid close attention to. Uncovering the formation mechanism and the stability rule of the doped clusters are beneficial to provide theoretical basis for preparation of new materials.In this paper, we investigate the structures and stability of AISn (n=1-10) clusters. The geometric configurations and electronic structures of the clusters are studied using the B3LYP(DFT) method at6-311G**level. The ground state structure, vibrational frequency, charge transfer and bonding characteristic of the doped clusters are discussed in detail. Woreover, HOMO-LUMO energy gap, electron affinity energy and the second difference in cluster total energies are studied. The results show that the ground state of AIS2is a linear structure with a center aluminum atom, while other AISn(n=3-10) are the combination of a S2or S3ring and a Sm(m<n) ring shared with one Al atom. AIS2, AIS4and AIS9are more stable by analyzing the energetic of the ground state structures.The geometric configurations and stability of AISn±(n=1-10) clusters have been calculated by the same theory level. We discuss the changing rules of the structure feature concerned by rearching HOMO-LUMO energy gap, dissociation energies and the second difference in cluster total energies. The results show that the ground states of AISn±(n>2) are mainly the combination of Smand Sn-m(m<n) rings shared with one Al atom, that formed AlcoreSshell planar or solid structures. The molecular orbitals are mainly composed of Al s-and p-states mixed with S p-states. These AISn±(n=1-10) clusters with even n possess are relatively higher dynamic stability by analyzing dissociation energies and the second difference in cluster total energies.The geometric structures and stability of Al2Sn/Al2Sn±(n=1-10) clusters are also studied by the B3LYP (DFT) method. We found that the ground states of neutral and ionic clusters (n<4) are linear or planar structures, while other clusters (n≥4) are mainly staggered three-dimensional structures. The coordination numbers are2、3and4for most Al atoms and2for most S atoms in the structures. In the neutral clusters, AlS2AIS4and AIS9are more stable, while ionic clusters’maximum peaks are observed for Al2Sn+and Al2Sn-clusters at n=2,4,6,9and n=2,4,6,8respectively on the size dependence for the various energies.