  Using {\it ab initio} total energy density-functional theory calculations, we
investigate the electronic, structural and magnetic properties of Manganese
doped Germanium nanowires. The nanowires have been constructed along the [110]
direction and the dangling bonds on the surface have been saturated by hydrogen
atoms. We observed that the Mn has lower formation energy at the center of the
wire when compared to regions close to the surface. The Mn-Mn coupling has
lower energy for a high-spin configuration except when they are first nearest
neighbors. These results show that Ge:Mn nanowires are potential candidates for
ferromagnetic quasi-one dimentional systems.
