Chemical Inhomogeneity, Short‐Range Order, and Magnetism in the LiNiO 2 ‐NiO Solid Solution

NiO:Li is an early exemplar for which hole‐doping of a correlated insulator gives rise to rich and varied magnetic behavior. It is also an important system from the viewpoint of p‐type transparent conducting oxides, and is representative of a large class of materials that have been used in lithium ion batteries, since the end‐member compound, LiNiO 2 , belongs to the class of layered cathode materials. Despite the deceptive structural and compositional simplicity of this system, a complete understanding of its complex magnetic properties has remained elusive. Here a comprehensive investigation of the solid solution Li x Ni 2− x O 2 , examining samples of precise stoichiometry using a combination of high‐resolution synchrotron X‐ray powder diffraction and SQUID magnetometry, is provided. The focus is on the interesting region between 0.40< x