Darstellung und Kristallstruktur von K₄₉Tl₁₀₈ / Preparation and Crystal Structure of K₄₉T1₁₀₈

Abstract

K 49 T1 108 was prepared from the elements (molar ratio K: Tl = 1:2) at 700 K. The crystal structure was determined by single crystal X-ray diffraction methods (a = 1728.7(1) pm, Pm 3, Z = 1, R = 0.086). It contains T1 12 icosahedra and Tl 12 truncated tetrahedra (Kasper polyhedra). 20 truncated tetrahedra form Tl 84 -polyhedra (Samson polyhedra) by sharing hexagonal faces. These polyhedra are connected by common edges. Folded Tl 13 -chains connect the icosahedra and the Samson polyhedra to a framework. The truncated tetrahedra are occupied by potassium atoms.