Magnetic susceptibility studies of LiNiO2and NaNiO2

The temperature variation of the magnetic susceptibility of the compounds LiNiO 2 and NaNiO 2 has been measured. Contrary to a previous report by Hirakawa and co-workers (1985), which claimed that these materials were antiferromagnetically coupled, and so could potentially possess quantum liquid ground states, the authors' data suggest that these materials behave as weakly coupled 2D Ising ferromagnets. They show that this conclusion is in fact support by much of the data in the previous report.