Revision of the crystal structure and cation distribution of LiMn2-yTiyO4 (0 < y ≤ 1.0) spinels

The dependences of observed unit cell parameter aobs, oxygen parameter uobs, tetrahedral L(A)obs, and octahedral L(B)obs bonds in LiMn2-yTiyO4 (0≤y≤1) spinels, on the Ti content y, have been extracted from a set of published powder X-ray and neutron diffraction data. The observed parameters have been compared to their theoretical counterparts acalc, ucalc, L(A)calc and L(B)calc, predicted by two cation distributions: (Li1−t+Tit+4)[Lit+Mn+3Ti1−t+4)O4 – model (I), and (Li1−m+Mnm+2)[Lim+Mn1−2m+3Mn1−y+m+4Tiy+4]O4 – model (II), proposed earlier. Substantial discrepancies between observed and calculated data disclosed the inconsistency of model (I). On the contrary, oxygen parameters and bond lengths, predicted by Model (II), are in good agreement with the observed data.