Theoretical investigation of structural and electronic properties of C20Li nanowire

We investigated electronic and structural properties of C20Li nanowire by first-principle calculations. The optimum adsorption position of Li on C-20 was found to be the bridge position by comparing the total energies of the adsorbed structures. We constructed C20Li nanowire by using Li adsorbed on C-20 at the bridge position as the building block. The nanowire has two local equilibriums at a(eq) = 7.8 and 8.4 angstrom and shows ductile behavior under mechanical stress since the system utilizes all adsorption positions to relieve the strain. The on-top adsorption is observed in over-stretched nanowires while the pentagon site is preferred in over-compressed nanowires. In view of its flexible structure, C20Li may be incorporated in a matrix without inducing strain. The system is semiconductor with energy gap values E-g < 1 eV for both aeq equilibrium lattice values. Since the highest occupied band becomes unoccupied for minority spin, spin polarization of 1 mu(B) per formula unit is observed. C20Li may be utilized as the building block of magnetic semiconductors.