Thio-hydroxoanionen des Germaniums: Darstellung, Struktur und Eigenschaften von Na2GeS2(OH)2 · 5 H2O / Thio-hydroxo Anions of Germanium: Preparation, Structure and Properties of Na2GeS2(OH)2 · 5 H2O
Abstract Pure thio-hydroxo-germanates can be prepared from aqueous solutions by reactions of stoichiometric amounts of either sodium sulfide and GeO2, or NaOH and GeS2. The preparation of colourless crystalline Na2GeS2(OH)2 · 5 H2O is reported. The compound is characterized by a single-crystal X-ray structure analysis. It is orthorhombic, space group Pbcn, with a = 10.752(2), b= 13.787(2), c = 14.150(2) Å. The structure contains novel monomeric GeS2(OH)22- anions with Ge-S bond distances of 2.150(1) and 2.145(1) Å and with Ge-O lengths of 1.809(3) and 1.815(3) Å. An extensive S ··· HO-and O -HO-hydrogen bond system connects the anions with the octahedrally coordinated Na+ ions. The vibrational spectra are reported. The symmetric GeS2 andGeO2 stretching vibrations in the anion are observed at 415 and 618 cm-1.