The crystal structures of the lithium hydroxide halides Li4(OH)3Br and Li4(OH)3I

Using single crystal analysis and powder diffraction data the crystal structures of the Lithium hydroxide halides Li-4(OH)(3)Br and Li-4(OH)(3)I were solved and refined. Li-4(OH)(3)Br crystallises in the space group P2(1)/m and is isotypic with the lighter homologue Li-4(OH)(3)Cl. (Rietveld-refinement; T = 293 K: a = 545,41(1); b = 758,13(1); c = 650,20(1) pm; beta = 93.82(1)degrees : Z = 2; 300 unique reflections; R-p = 0.106; R-wp = 0,109; R-exp = 0,081). Li-4(OH)(3)I crystallises in the space group Pmmn in a variant of the LiOH structure in which 1/4 of the hydroxide anions are replaced by iodide anions. (Single crystal analysis; T = 100 K; a = 1029,5(4): b = 525,9(2): c = 573,2(2) pm; Z = 2; 392 unique reflections: R-1 = 0,0642).