| Abstract: | New Oxocobaltates(IV): On K6[Co2O7] K6Co2O7 is another new oxide containing tetravalent Co (red-violet single crystals). According to precession- and WEISSENBERG-photographs the space group is P21/c; a = G.585, b = 9.123. c = 11.479 Å, β = 127.1°. The crystal structure shows Co2O7-groups (two tetrahedron connected by a common corner, symmetry ≈ S6). The Madelung Part of Lattice Energy (MAPLE) is computed and compared with MAPLE of Cs2CoO3. The magnetic properties are reported (measurements of susceptibility by the method of FARADAY in a temperature range of 3–300°K). |
