Calculation of the anisotropic magnetoelastic coupling constants in iron

Abstract

Formulae for the anisotropic magnetoelastic coupling constants B1 and B2 related to shear strains in itinerant electron ferromagnets with cubic symmetry are derived by the perturbation theory where a tight-binding parametrisation scheme for the electron-ion and spin-orbit couplings is used. Numerical computations of B1 and B2 are carried out for iron. The results are compared with the empirical values estimated by the phenomenological theory and the agreement between them is satisfactory for B1 but not for B2. The discrepancy is discussed.