Germanium IV Fluoride

Ge02 + 6HF - H2GeF6 + 2H20 H2GeF6 + BaCl2 -4 BaGeF6 + 2HC1 

There appears to be only one really satisfactory method for preparing pure germanium(IV) fluoride. This method involves the thermal decomposition of barium hexafluoro-germanate1 in a quartz or Vycor tube, a method analogous to that described for the preparation of silicon tetrafluoride (synthesis 47). Germanium(IV) fluoride has also been produced by the fluorination of germanium(IV) chloride with antimony (III) fluoride 2 however, it is necessary to distill fractionally the mixture of chlorofluorides resulting from the reaction. 

Five and twenty-three hundredths grams of germanium(IV) oxide (0.05 mol) is dissolved in 15 ml. of a concentrated aqueous solution of hydrofluoric acid (47 %). A platinum evaporating dish or a polyethylene plastic beaker is used to keep silicon contamination to a minimum. A solution of 10.5 g. of barium chloride (0.05 mol) in 50 ml. of water is added. Barium hexafluorogermanate forms as a white, granular precipitate, which is filtered and washed free of chloride. The product is dried by heating to 300° in vacuo and is stored in a desiccator over phosphorus(V) oxide. The yield is 15.24 g. (94%). 

The yield will depend on how long the decomposition is allowed to proceed. A yield of approximately 50%, based on BaGeFg, is normally obtained. Spectroscopic examination indicates that the product is at least 98% pure. 

At room temperature germanium (IV) fluoride is a colorless, fuming, pungent gas with an odor somewhat like that of garlic. At elevated temperatures it is reduced by copper.1,2 The vapor pressure of the solid is appreciable at temperatures as low as —111.7° and becomes approximately equal to atmospheric pressure at — 36.5°.1 The liquid which forms under increased pressure is clear, colorless, and mobile. The triple point is at —15° and 3032 mm. pressure. 

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Germanium(IV)-fluorid wird von Wasser wie SiF4 leicht aufgenom-men. Dabei entsteht Germaniumfluorwasserstoffsaure H2[GeF6] ... 

Barium hexafluorogermanate(IV), preparation of, for decomposition to germanium (IV) fluoride, 4 147... 

Halide complexes of Group 14 metals continue to offer surprises in their structural chemistry. A new fluoro complex of germanium GeyFig has been isolated from the decomposition of germanium(IV) fluoride and shown by crystallography to comprise sheets of [GegFio] clusters... 

Germanium(IV) fluoride GeE4 -50 Iron(III) nitrate nonahydrate Ee(N03)3-9H20 +15200... 

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