Stable structures for Si-20 clusters - art. no. 023201

Full-potential linear-muffin-tin-orbital molecular-dynamics calculations ha ve been performed to investigate the structures and energies of Si-20 clust ers. Among the selected 15 stable structures for Si-20, the most stable str ucture is constructed by stacking Si-9 tricapped trigonal prisms (TTP) subu nits. Its symmetry is C-2 Another structure with almost the same binding en ergy as the ground-state structure is also obtained by stacking Si-9 tricap ped trigonal prisms subunits, but its symmetry is D-3h The subunit is just the ground-state structure of Si-10, with C-3v symmetry. The ground-state s tructure of Si-20 can interpret the fragmentation experimental result and t he absorption property of ammonia molecules for Si-20(+).