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Using inelastic X-ray scattering beyond the dipole limit and hard X-ray photoelectron spectroscopy we establish the dual nature of the U 5 f electrons in U M 2 S i 2 (M = Pd, Ni, Ru, Fe), regardless of their degree of delocalization. We have observed that the compounds have in common a local atomic-like state that is well described by the U 5 f 2 configuration with the Γ 1 ( 1 ) and Γ 2 quasi-doublet symmetry. The amount of the U 5 f 3 configuration, however, varies considerably across the U M 2 S i 2 series, indicating an increase of U 5f itineracy in going from M = Pd to Ni to Ru and to the Fe compound. The identified electronic states explain the formation of the very large ordered magnetic moments in U P d 2 S i 2 and U N i 2 S i 2 , the availability of orbital degrees of freedom needed for the hidden order in U R u 2 S i 2 to occur, as well as the appearance of Pauli paramagnetism in U F e 2 S i 2 . A unified and systematic picture of the U M 2 S i 2 compounds may now be drawn, thereby providing suggestions for additional experiments to induce hidden order and/or superconductivity in U compounds with the tetragonal body-centered T h C r 2 S i 2 structure. 

Exchange bias (EB) is highly desirable for widespread technologies. Generally, conventional exchange‐bias heterojunctions require excessively large cooling fields for sufficient bias fields, which are generated by pinned spins at the interface of ferromagnetic and antiferromagnetic layers. It is crucial for applicability to obtain considerable exchange‐bias fields with minimum cooling fields. Here, an exchange‐bias‐like effect is reported in a double perovskite, Y₂NiIrO₆, which shows long‐range ferrimagnetic ordering below 192 K. It displays a giant bias‐like field of 1.1 T with a cooling field of only 15 Oe at 5 K. This robust phenomenon appears below 170 K. This fascinating bias‐like effect is the secondary effect of the vertical shifts of the magnetic loops, which is attributed to the pinned magnetic domains due to the combination of strong spin–orbit coupling on Ir, and antiferromagnetically coupled Ni‐ and Ir‐sublattices. The pinned moments in Y₂NiIrO₆are present throughout the full volume, not just at the interface as in conventional bilayer systems.