Ab Initio Study on the Structural and Magnetic Properties of Co-Pd and Co-Pt Linear and Zigzag Nanowires

Based on the projector augmented-wave method, the self-consistent electronic structure calculations were carried out on pure Co and mixed Co-Pd and Co-Pt free-standing linear and zigzag nanowires. The calculations reveal that the bond lengths for all these systems are generally increased as their structures change from the linear to the zigzag chain. The bond lengths for Co-Pd and Co-Pt wires are in between the values of corresponding pure system and the bond angles around 60 degrees suggesting the possible formation of Co-Pd and Co-Pt bimetallic materials. In mixed Co-Pd and Co-Pt chains, the Co, Pd and Pt atoms have quite high local magnetic moments. The calculations suggest that the magnetic moments in linear nanowires are generally larger than the ones of corresponding zigzag nanowires. It is found that there is hybridization between Co 3d and Pd 4d, Co 3d and Pt 5d states, which may significantly affect structural stability and magnetism of Co-Pd and Co-Pt nanowires.