Figure 9
The projections of atomic positions of the β-Mn structure on the (001) plane. These projections coincide (by neglecting small distortions) with the part of the {3, 3, 5} polytope projection shown in Fig. 3. (a) Atomic positions in the β-Mn unit cell with contours of double spirals only: vertices of the CBT and winding helices correspond to the D, C and B vertices of the polytope {3, 3, 5} in Fig. 3(a). (b) Projections of atomic positions in the β-Mn structure in (a) are disposed (by neglecting small differences) on the circumferences containing projections of the {3, 3, 5} polytope vertices, these vertices belonging to the D, C and B triacontahedra in Fig. 3. (c) The correspondence of the local 8/3 axis in the β-Mn structure to the 30/11 axis in the {3, 3, 5} polytope. The rotation of three vertex pairs of the star polygon {30/11} by 3, 6 or 9° along the D circumference (b) gives rise to the 8/3 polygon with vertices in positions occupied by Mn ions of two charge states designated as grey and white balls. |