Inelastic magnetic X-ray scattering from highly correlated electron systems: La1.2Sr1.8Mn2O7, La0.7Sr0.3MnO3 and Fe3O4 Original Research Article

Magnetic Compton profiles have been measured for the colossal magnetoresistance manganites La1.2Sr1.8Mn2O7 and La0.7Sr0.3MnO3, and for magnetite Fe3O4, along various crystallographic directions, over a wide range of temperatures and magnetic fields. The experimental results are interpreted via first-principles computations for the double layer manganite, La1.2Sr1.8Mn2O7, and by using a simple model involving atomic d-orbitals and free electrons for the other two compounds. For all three materials a preference for the occupation of eg orbitals is found, particularly, for orbitals of dx2−y2dx2−y2 symmetry. An itinerant electron contribution is adduced at all temperatures in magnetite; such a contribution also appears in La1.2Sr1.8Mn2O7, but it is present only at low temperatures in La0.7Sr0.3MnO3.