Magnetic properties of Fe-Rh alloys

We performed first-principles calculations on molecular clusters with the d iscrete variational method, in the spin-polarized case, to study the magnet ic properties of Fe-Rh alloys. In ordered FeRh, our results showed a nearly constant local moment for both iron and rhodium atoms, in the ferromagneti c phase, for a wide range of lattice spacings. By shrinking the lattice, on e observes the collapse of the magnetic moment for Fe and Rh atoms, in both ferromagnetic and antiferromagnetic phases. Our results showed a strong de pendence of the hyperfine magnetic field at the iron sites on the atomic co nfigurations in their neighborhood. A loss of magnetic coupling is expected by adding Rh atoms in the immediate vicinity of the iron sites. (C) 2001 A merican Institute of Physics.