Li2I(OH): Eine Verbindung mit eindimensional unendlich kantenverknüpften [Li4/2(OH)]+-Pyramiden

Li₂I(OH): A Compound with Onedimensional Infinite Edge Sharing Li_4/2(OH)⁺] Pyramids The pseudobinary system LiOH/LiI was investigated by X-ray methods. Two compounds, Li₂I(OH) and Li₅I(OH)₄ exist. The structure of Li₂I(OH) was solved by single-crystal data. For Li₅I(OH)₄ lattice constants and space group symmetry are given: Li₂I(OH): Pnma, Z = 4, a = 10.339(4) Å, b = 5.567(1) Å, c = 6.643(2) Å, Z(F_o) mit (F_o)² ≧ 3σ(F_o)² = 439, Z (parameter) = 23, R/R_w = 0.030/0.040 Li₅I(OH)₄: Pmmn or P2₁mn(= Pmn2₁), Z = 2, a = 10.42 Å, b = 5.30 Å, c = 5.81 Å Li₂I(OH) crystallizes in a new type of structure. The motif of a distorted hexagonal close-packed arrangement of iodide ions is penetrated by chains of Li_4/2(OH)⁺].