Spin and orbital moments in U3X4-type pnictides (X = P, As, Sb, Bi): Polarized neutron-diffraction study

Polarized neutron experiments have been performed on single crystals of U3P 4, U3As4, U3Sb4, and U3Bi4 The spin and orbital components of the magnetic moments on the uranium atoms were separated within the dipole magnetic form factor approximation and compared to the theoretical values. The ratio of these components indicates an important hybridization of 5f-electron states with the conduction band for all four compounds. The hybridization estimat ed in this way differs significantly for two uranium sublattices in U3Sb4 [ S0163-1829(99)01533-7].