X-ray acid neutron powder diffraction studies have been made on phase-
pure LiNixMn2-xO4 (x = 0, 0.04, 0.18 and 0.33) substituted materials s
olely to establish how Ni substitutes into the spinel structure. Rietv
eld refinement showed all the materials to have the spinel phases (spa
ce group: Fd3m) with lithium occupying the tetrahedral (sa) sites, and
Ni substituting for Mn at the octahedral (16d) sites. The cubic latti
ce parameter (a) decreases on Ni substitution: a = 8.251(4), 8.241(3),
8.219(3) and 8.196(3) Angstrom for x = 0.0; 0.04, 0.18 and 0.33, resp
ectively. (C) 1998 Elsevier Science B.V. All rights reserved.