Zur Kristallstruktur von CaFeF₅

Abstract

On the Crystal Structure of CaFeF 5 Single crystals of CaFeF 5 were obtained by heating a mixture of the component fluorides at 860°C for 12 d (a = 549.2(1), b = 1007.6(2), c = 759.9(2) pm, β = 110.02(3)°; space group P2 1 /c, Z = 4). The X‐ray structure redetermination of a twinned specimen confirmed the chain structure of octahedra sharing trans corners already known. But the anomalies reported earlier were removed and less distorted [FeF 6 ] octahedra and [CaF 7 ] pentagonal bipyramids were found, the distances of which are split within the usual range around mean values of Fe—F: 192.4 and Ca—F: 233.1 pm.