Fig. 2. (a) A water cluster formed in the layered Mn2O4·(H2O). The numbers next to the dotted lines in bold denote the distance. (b and c) MnO6 octahedra and nearby crystal water molecules for the (b) layered and (c) spinel Mn2O4·(H2O). The italicized numbers are the variation in charge density and the unitalicized numbers are bond distances. The charge densities are integrated by the Bader method. (d–f) The PDOS of (d) empty spinel Mn2O4, (e) spinel Mn2O4·(H2O)0.25 and (f) layered Mn2O4·(H2O)0.25. The upper and lower halves of each panel are spin up (majority) and down, respectively. The isolated H2O is presented together in (d). (g) The magnetic moments of Mn in the spinel and layered Mn2O4·(X)0.25n. The value for Mn3+ in Mn3O4 (3.93) is presented with a dashed line for comparison. (h) The change in lattice parameters in spinel Mn2O4·(X)0.25n.
