Electronic and Magnetic Properties of Linear and Dimerized Titanium Nanochains Under Compressive and Tensile Strain

The magnetic and electronic properties of both linear and dimerized nanochains of titanium at different atomic distances are calculated within density functional theory with the generalized gradient approximation. Titanium which is a nonmagnetic in its bulk form is shown to become magnetic in its nanochain structure. Also, a close relationship is found between magnetic state and geometry of chain structure and the dependence of electronic properties on the atomic structures of chains is revealed. It is found that, for dimerized nanochains from equilibrium constant, compressive strain leads to a reduction in magnetism. Moreover, characteristics of the systems near the Fermi level are investigated and the charge densities of both nanostructures are studied in the ferromagnetic order. The results show that metallic bonding is mainly responsible for the linear structure; however, for the dimerized structure, the bonding is more directional, i.e. has a more covalent character. With increasing tension along the axis of the nanostructures, a change in the types of bonding is found.