  In this work we study the structural stability and electronic properties of
the Beryllium sulphide nanowires (NWs) in both zinc blende (ZB) and wurtzite
(WZ) phases with triangle and hexagonal cross section, using first principle
calculations within plane-wave pseudopotential method. A phenomenological model
is used to explain the role of dangling bonds in the stability of the NWs. In
contrast to the bulk phase, ZB-NWs with diameter less than 133.3 (angstrom) are
found to be less favorable over WZ-NWs, in which the surface dangling bonds
(DBs) on the NW facets play an important role to stabilize the NWs.
Furthermore, both ZB and WZ NWs are predicted to be semiconductor and the
values of the band gaps are dependent on the surface DBs as well as the size
and shape of NWs. Finally, we performed atom projected density-of states
(PDOSs) analysis by calculating the localized density of states on the surface
atoms, as well as on the core and edge atoms.
