Magnetic structure of Li 1 − xNi 1 + xO 2
نویسنده
چکیده
We study the magnetic structure of layered Li1−xNi1+xO2 and propose a new scheme: the AF interaction between the excess Ni in the Li layers and the Ni ions in the Ni planes, gives rise to the formation of ferrimagnetic clusters, which control the physics of these systems. The values of the different interactions are estimated from a mean field calculation in the high temperature limit. For the small x samples studied here the method does not yield an accurate value of JAF, but it is very sensitive to the intralayer interactions, allowing to conclude that they are ferromagnetic. The recent proposal of a quantum spin-orbital liquid in this system is discussed and the comparison with Jahn-Teller distorted NaNiO2 is made. PACS. 75.10.-b General theory and models for magnetic ordering – 75.30.Et Exchange and superexchange interactions
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