Synthesis, structure and physical properties of LixNa1−xNiO2

Solid solutions of LixNa1−xNiO2 were synthesized and their structures were determined by Rietveld analysis using time-of-flight (TOF) neutron diffraction data. Three phases were observed: monoclinic (C2/m) phase with x=0.00, rhombohedral(I) (R3̄m) phase with 0.13<x<0.15, rhombohedral(II) (R3̄m) phase with 0.70<x<1.00. Rietveld analysis of the rhombohedral(I) phase indicated no Ni disordering at the Li/Na (3a) site, and the disappearance of the cooperative Jahn–Teller ordering corresponds to the distance changes between the adjacent Ni layers. Magnetic properties were also measured for these phases.