Figure 3
Structure of kermesite; projection along the b vector of Kupčík's cell: (a) in the ball-and-stick model, (b) represented by coordination polyhedra. Note Sb atoms located outside the centers of the polyhedra due to the stereochemical activity of lone electron pairs. Delimitation of OD layers as well as λ-ρ and σ-ρ planes are indicated. This structure corresponds to the MDO1 (4A) polytype. |