Dzyaloshinskii-Moriya interaction H adsorption H diffusion Heusler alloy MgBi2O6 Mo doping Nb (100) surface Prussian blue analogue bulk CrSi2 covalent hybridization doping electronic property electronic structure equiatomic quaternary Heusler compounds exchange energy first principles first-principle first-principle calculations first-principles calculation first-principles calculations first-principles method half-metallic material half-metallic materials half-metallicity interface structure lattice dynamics magnetic anisotropy magnetic properties magnetism mechanical anisotropy