Darstellung und strukturelle und spektroskopische Charakterisierung der Triiodide [M(12-Krone-4)2]I3 mit M = Na und Rb / Preparation and Structural and Spectroscopic Characterization of Triiodides [M(12-Crown-4)2]I3 with M= Na and Rb

TLDR: The lattice parameters are a = 8:505(2), b = 14:280(3), c = 10:695(2) A and α = 89:86(2)-°, β = 80:00° and γ = 85:90° for 1 and 2, respectively.

Abstract: Reddish-brown crystals of [Na(12-crown-4)₂]I₃ (1) and [Rb(12-crown-4)₂]I₃ (2) were formed through the reaction of NaI or RbI, I₂ and 12-crown-4 in ethanol. Both structures are triclinic, space group P1 with Z = 2. The lattice parameters are a = 8:505(2), b = 14:280(3), c = 10:695(2) A and α = 89:86(2)°, β = 80:00(2)° and γ = 85:90(2)°; and a = 10:694(2), b = 11:598(2), c = 12:718(2) A and α = 71:00(2)°, β = 86:97(2)° and γ = 67:710(10)° for 1 and 2, respectively. Both crystal structures contain one independent complex cation without crystallographic symmetry. The anionic parts of both structures consist of two crystallographically independent, isolated, triiodide anions I₃⁻ with crystallographic inversion symmetry. The cations are distorted sandwich-like complexes with two 12-crown-4 molecules surrounding the alkali metal atom in the center.