Germanium arsenic compounds

A short time ago numerous triorganyl-cyclotriphosphanes have become accessible as pure substances on various synthetic routes (2). Moreover, three-membered phosphorus heterocycles with carbon, silicon, germanium, arsenic, boron, and sulfur as hetero ring atoms could be synthesized (2). Recently, we have found that such compounds with elements of the fifth periodtare als stable enough fop existence. Through the reaction of K(Bu )P-P(Bu )K with Bu S C1 or Bu -SnC at -78°C, the diphosphastib rane ... 

The pH range of acid leaching and the iron concentration in solution are controlled in order to maximize the precipitation of arsenic from solution. It is presumed that iron-arsenic compounds are formed, which are not soluble in acid. The increased rejection of arsenic to the residue at this stage also helped to improve the efficiency of impurity metals (including germanium) removal in the subsequent neutral leaching step. 

As with mono-substituted compounds, the direct attachment of elements with vacant d orbitals can lead to a substantial frequency reduction. Sacher et al. [42] have examined a number of derivatives with the alkyne link attached to silicon, germanium, arsenic, antimony etc. and find the C=C stretching band in the 2193—2156 cm range. A number of references to similar work are given by Bellamy [15]. 

HG/LT-GC/ICP-MS. This analytical technique enabled the identification of organometal(loid) compounds in human urine species of the six elements germanium, arsenic, selenium, tin, antimony, and mercury were determined... 

Sudden change in the composition of As 3d peak is observed at the same temperature of 500°C there apvpears another arsenic compound with germanium. The peak fitting component designated as C2, is shifted by 0.8 eV in relation to the bulk component B (Fig. 17). The similar state of arsenic is described in (Studd et al., 1983) for germanium arsenide... 

Arsenic from the decomposition of high purity arsine gas may be used to produce epitaxial layers of III—V compounds, such as Tn As, GaAs, AlAs, etc, and as an n-ty e dopant in the production of germanium and silicon semiconductor devices. A group of low melting glasses based on the use of high purity arsenic (24—27) were developed for semiconductor and infrared appHcations. 

Unsolvated organomagnesium compounds have been recommended for the synthesis of organometallic derivatives of mercury, boron, aluminum, silicon, germanium, tin, phosphorus, arsenic, and antimony6-8 and have been used in procedures for the alkylation of aromatic rings and for the production of various polymerization catalysts.4 9... 

Both alkyl and aryl metals have been studied, but not a very wide range of compounds. Several studies of triphenylarsene and triphenylstibine have been done. Methyl and ethyl compounds of arsenic, germanium, mercury, bismuth, and lead essentially complete the list. In virtually all cases the results have been clouded by difficulties in effecting chemical separation without altering the product distribution. The results do, nonetheless, lead to valid and important conclusions. 

Aminolysis of the corresponding halides is the preferred method for the synthesis of dialkylamino derivatives of boron,1 silicon,2 germanium,3 phosphorus,4 arsenic,5 and sulfur.6 (Dialkylamino) chlorosilanes are prepared stepwise by the reaction of silicon tetrachloride with dialkylamines. This method may be utilized equally well for the conversion of alkyl- or aryl-substituted halides [e.g., (CH3) SiCl4. ] or of oxide and sulfide halides (e.g., POCl3 or PSC13) to the corresponding dialkylamino compounds. 

The application of these techniques has led to the discovery of a number of organometallic species of arsenic, tin, and antimony in the marine environment. Germanium has not been observed to form organometallic compounds in nature. Some aspects of the geochemical cycles of these elements which have been elucidated by the use of these methods are discussed. 

It is now well established that organometallic compounds are formed in the environment from mercury, arsenic, selenium, tellurium and tin and hence were also deduced on the basis of analytical evidence for lead, germanium, antimony and thallium. Biological methylation of tin has been demonstrated by the use of experimental organisms. Methylgermanium and methyllead were widely found in the environment but it is debatable whether germanium and lead are directly methylated by biological activity in natural environment. 

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