The exchange-correlation functional is approximated by Perdew-Burke-Ernzerhof (PBE) representation of generalized gradient approximation (GGA). Geometry optimization is carried out using the conjugate gradient (CG) algorithm with 1×1×4 k-grid Monkhorst pack until the atomic forces were converged to 0.01 eV /Å. A mesh cut-off 300 Ry is used. A vacuum of 12 Å is used along the non-periodic directions to avoid interaction between periodic replicas of the system. The spin-dependent electron transport properties are calculated using T ranSIEST A code adopting NEGF-DFT method in the spirit of Landauer-Büttiker formalism. For transport calculations Monkhorst-pack of 1×1×100 k-grid in x, y and z directions is used. The coupling of left/right electrodes to the scattering region is taken into account using self-energies denoted as Σ L,R . The level broadening due to coupling between the scattering region and left/right electrodes is given by