Germanium tetrafluoride

Germanium tetrafluoride produces hydrogen fluoride in aqueous acidic solutions. Hydrogen fluoride is toxic and very corrosive. The OSHA permissible exposure limit (17) and the American Conference of Governmental Industrial Hygienists (ACGIH) TLV for fluoride is 2.5 mg/m of air (18). 

Sfi.F-Test D.4A Write the formulas for (a) vanadium(V) oxide (b) calcium carbide (c) germanium tetrafluoride (d) dinitrogen trioxide. 

McCarron, E. M. et al., J. Chem. Soc., Chem. Comm., 1980, 890-891 The solid product of intercalating graphite with germanium tetrafluoride-fluorine mixtures at 20°C is thought to have an oxidising and fluorinating capability close to that of elemental fluorine itself. 

The solid product of intercalating graphite with germanium tetrafluoride—fluorine mixtures at 20°C is thought to have an oxidising and fluorinating capability close to that of elemental fluorine itself. 

This suggests that selenium tetrafluoride is able to act as a fluoride-ion donor and that the adduct with palladium tetrafluoride is the salt (SeF3+)2[PdFg]2 . Since the platinum tetrafluoride and germanium tetrafluoride adducts are isomorphous with the palladium P compound they should also be given the ionic formulation. 

The discovery of what appears to be a thermodynamic threshold governing the intercalation of graphite by fluoro anions, MF,, has required the evaluation of the thermodynamic stability of a number of such species. Since germanium tetrafluoride and fluorine are intercalated, in combination, by graphite to form both GeFj" and GeFs ", the first and second fluoride ion affinities of that molecule are each of interest. Evaluation of the fluoride ion affinity of boron trifluoride by Altshuller yielded a value of-71 kcal moF. This has been accepted by several authors as the basis for other fluoride ion affinities and electron affinities. Sharpe, however, has preferred a value of -91 kcal moF, based upon the data of Bills and Cotton. Although this latter value is in harmony with other fluoride ion affinities and electron affinities, its confirmation was clearly desirable to provide a firm basis for correction of affinities based upon the lower value. This paper describes the studies that have provided these fluoride ion affinities. 

FeTeO.9 IRON 0.9-TELLURIDE 724 GeF4[g] GERMANIUM TETRAFLUORIDE (GAS) 769... 

Germanium tetrafluoride is stored in glass bottles or, better, sealed under pressure in quartz ampoules. 

COORDINATION OF SILICON AND GERMANIUM TETRAFLUORIDE WITH SOME OXYGEN DONORS. 

Few coordination compounds of silicon and germanium tetrafluoride have been prepared and characterized. MUETTERTIES (1) has described SiF [(CH ) SO] and SiF [(CH )2NCHO]2 and the corresponding complexes of germanium tetrafluoride. ISSLEIB and REINHOLD (2) have prepared SiF [(C Hg) PO], ... 

SiFl(C,H J POL, SiFlfCH ) NOL and SiFiC H NOL. The interaction of silicon tetrafluoride with methanol has been shown recently to involve strong hydrogen bonds between fluorine atoms and hydroxyl protons rather than octahedral coordination of silicon (3). We have now examined the relative tendency of silicon and germanium tetrafluoride to complex with simple ethers, acetone, and methanol. 

Combining ratios of germanium tetrafluoride with ethers, acetone, and methanol were obtained by tensimetric titration and quantitative synthesis. These values are shown in the following table together with analytical data and melting points. 

The following striking differences between silicon and germanium tetra-fluoride are apparent (i) germanium tetrafluoride forms more stable complexes with cyclic ethers and dimethyl ether than does silicon tetrafluoride ... 

At 180° C trifluoromethyltriiodogermane slowly decomposes, a Fording germanium tetrafluoride and tetraiodide, fluoroolefins, and cyclic fluorocarbons. The nature of these products suggests the occurrence of the reactions,... 

These properties are similar to those of germanium tetrafluoride. Aqueous sodium hydroxide reacts at room temperature with the three CFsGeXa compounds to give fluoroform. Similar behavior is shown by perfluoroalkyl derivatives of tin and lead. With cold water the Cp3GeX3 derivatives afford stable clear solutions, although the iodo compound is not immediately miscible. On addition of potassium fluoride solution the novel salt K2[CF3GeF5] is produced, but unlike K[CF3BF3] it is unstable to base. 

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