Die Kristallstrukturen der Eisen- und Cobalt-Hexacyanokomplexe Rb2LiM(CN)6 und Rb2NaM(CN)6 / The Crystal Structures of the Iron- and Cobalt-Hexacyanocomplexes Rb2LiM(CN)6 and Rb2NaM(CN)6

Abstract

Abstract The crystal structures of four isotypic cyano complexes, belonging to the monoclinic type of cryolite (P21/n, Z = 2), were determined by single crystal X-ray methods and in one case also by neutron diffraction: Rb2LiFe(CN)6 (a = 717.3, b = 748.0, c = 1030.2 pm, β = 90.24°; Fe - C = 193.6, C - N = 114.5, Li - N = 227.0 pm), Rb,NaFe(CN)6 (a = 724.5, b = 772.5, c = 1055.2 pm, β = 90.39°; Fe - C = 193.9, C - N = 114.2, Na - N = 250.4 pm), Rb,LiCo(CN)6 (a = 715.5, b = 741.2, c = 1025.0 pm, β = 90.14°; Co - C = 189.6, C - N = 114.3, Li - N = 226.9 pm), Rb2NaCo(CN)6 (a = 722.5, b = 766.3, c = 1049.2 pm, β = 90.33°; Co - C = 189.9 (188.8), C - N = 113.4 (7/5.5), Na - N = 250.6 (249.6 pm). The irregular [RbN8l coordination polyhedra exhibit average distances close to Rb - N = 336 pm. Details are discussed and the results compared with those of related compounds