Synthese und Kristallstruktur von Sr2Zn(OH)6 und Ba2Zn(OH)6

Synthesis and Crystal Structure of Sr₂Zn(OH)₆ and Ba₂Zn(OH)₆ Crystallization from supersaturated sodium hydroxozincate solutions by adding solutions of alkali earth metal hydroxides yields crystals of Sr₂Zn(OH)₆ and Ba₂Zn(OH)₆. The X-ray structure determination on these crystals was successful including all hydrogen positions: Sr₂Zn(OH)₆: P2₁/n, Z = 2, a = 5.794(1) Å, b = 6.160(1) Å, c = 8.141(1) Å, b = 91.23(1)°, N(F ³° 2σ F) = 1127, N(Var.) = 53, R₁/wR₂ = 0.047/0.081Ba₂Zn(OH)₆: P2₁/n, Z = 2, a = 6.043(1) Å, b = 6.336(1) Å, c = 8.451(2) Å, b = 91.23(2)°, N(F ° 2σ F) = 1669, N(Var.) = 54, R₁/wR₂ = 0.029/0.067. Sr₂Zn(OH)₆ and Ba₂Zn(OH)₆ crystallize isotypic in a distorted Li₂O structure type. Sr²⁺ resp. Ba²⁺ form a cubic primitive arrangement. Distorted octahedra of OH^– around Zn²⁺ fill therein alternating cubic gaps in an ordered way.