Neue Barium‐Antimonid‐Oxide mit den Zintl‐Ionen [Sb]3−, [Sb2]4− und [Sbn]n−

Abstract

AbstractNew Barium Antimonide Oxides containing Zintl Ions [Sb]3−, [Sb2]4−, and [Sbn]n−A new kind of chiral chains [Sbn]n− and O2− ions tetrahedrally coordinated by Ba are the characteristic anions in Ba3[Sb4][O] (monoclinic, space group P21/c, a = 696.4(2), b = 1280.7(3), c = 1294.1(3) pm, β = 112.39(1)°, Z = 4, R1 = 0.0399). Similarly, in RbBa4[Sb2][Sb][O], that crystallizes isotypic with KBa4[Sb2][Sb][O] (stuffed Cr5B3‐Typ, tetragonal, space group I4/mcm, a = 893.7(4), c = 1642.7(9) pm, Z = 4, R1 = 0.0508), the oxide ions occupy tetrahedral voids. The Zintl ions in this case are isolated [Sb]3− anions and dumbbells [Sb2]4− respectively. The new hydrid‐oxides Ba8[M]4[O][H]2 (M=Sb/Bi, tetragonal, space group I4/mmm, a = 515.34(12)/519.12(12), c = 3791.7(3)/3837.6(3) pm, Z = 4, R1 = 0.0319/0.0460) and Rb2Ba6[Sb2]2[Sb][O][H] (tetragonal, space group I4/mcm, a = 879.71(4), c = 2742.4(2) pm, Z = 4, R1 = 0.0592) can be structurally derived from the oxides Ba4Sb2O and RbBa4[Sb2][Sb][O] by intercalation (chemical twinning) of hydride antimonides. The synthesis of these air sensitive compounds exhibiting dark metallic luster was performed from melts of elemental Rb, Ba and Sb/Bi using Sb2O3/Bi2O3, BaH2 and Ba(OH)2 as sources for oxide/hydride. The detailed comparison of the structures and the results of FP‐LAPW band structure calculations show that the title compounds are electron precise Zintl phases with distinct band gaps.