Adsorbate-induced demagnetization: borohydride on magnetic substrates

Elucidating the effect of different adsorbates on the magnetic properties of substrates has found useful applications in the design of magnetic devices. In this paper, we show through first principles calculations that the adsorption of borohydride on magnetic substrates (pure 3d or first row transition metals such as Cr, Mn, Fe, Co, and Ni and Au-3d metal alloys) induces the demagnetization of the substrate atoms that directly bind with borohydride. We note a forward shifting of the spin-up and backward shifting of the spin-down components of the metal d band, before and after the adsorption of borohydride, demagnetizing the substrate. The inclusion of spin-polarization in the calculation affects the adsorption energy of borohydride but not its adsorption structure and relative energies on different substrates. Large substrate demagnetization is noted for substrates that promote the strong adsorption of borohydride.