R&D: Magnetic, Electronic, Mechanical and Dynamical Properties of Bimetallic M-Pt (M: Mn and Co) Alloys

SSRN has published an article written by Ndanduleni Lethole, Patrick Mukumba, and Golden Makaka, University of Fort Hare.

Abstract: “This work reports on the magnetic, electronic, mechanical and dynamical characteristics of the bulk L1 0 ordered M-Pt (M= Mn, Co and Ni) bimetallic alloys. All calculations were carried out using the first-principles approach within the Density Functional Theory (DFT) method and the Generalized Gradient Approximation (GGA) functional. The CASTEP simulation code as embedded in the Materials Studio software was employed to perform all the calculations. All the alloys were found to be thermodynamically stable and experimentally feasible due to the negative enthalpies of formation. The magnetic spins and electronic density of states showed that the MnPt alloy is highly magnetic over the CoPt and NiPt, respectively. The magnetic spin values for MnPt, CoPt and NiPt are 4.75 hbar/2, 3.00 hbar/2 and 0.98 hbar/2, respectively. MnPt and NiPt alloys were predicted to be mechanically and thermodynamically stable at ambient conditions since the elastic constants satisfied the Born stability conditions and there were no negative vibrations along high symmetry lines of the Brillouin zone in the phonon dispersion spectra. The CoPt alloy was found to be mechanically and dynamically stable from 13 GPa. More importantly, all M-Pt systems were predicted to be highly anisotropic, suggesting strong uniaxial magneto-crystalline anisotropy, making them very desirable for magnetic recording devices.“