Tellurium inorganic compounds

Inorganic Compounds. Inorganic selenium compounds are similar to those of sulfur and tellurium. The most important inorganic compounds are the selenides, haUdes, oxides, and oxyacids. Selenium oxidation states are —2, 0, +1, +2, +4, and +6. Detailed descriptions of the compounds, techniques, and methods of preparation, and references to original work are available (1—3,5,6—10, 51—54). Some important physical properties of inorganic selenium compounds are Hsted in Table 3. 

Tellurium forms inorganic compounds very similar to those of sulfur and selenium. The most important teUurium compounds are the teUurides, haUdes, oxides, and oxyacids (5). Techniques and methods of preparation are given in the Uterature (51,52). The chemical relations of teUurium compounds are iUustrated in Figure 2 (53). 

As a matter of fact, this book is concerned with sulfur, selenium, and tellurium as components of compound or solid solution systems in which metallic or semimetal-lic elements, whatsoever, participate as well. In particular, it is focused on the electrochemistry of the inorganic compounds of sulfur, selenium, and tellurium with metals and semimetals, which collectively may be termed as metal chalcogenide (MCh) systems. 

Various classes of organotellurium compounds in aprotic solvents have been studied as to their electrochemistry, whereas more limited are the reports on the electrochemistry of tellurium and its inorganic compounds in non-aqueous solvents [54, 55]. 

Wolfolk CA, Whiteley HR. 1962. Reduction of inorganic compounds with molecular hydrogen by Micrococcus lactilyicus. I. Stoichiometry with compounds of arsenic, selenium, tellurium, transition and other elements. J Bacteriol 84 647-58. 

As regards the nature of their action on a human organism, tellurium and its compounds are similar to the inorganic compounds of selenium and arsenic. Hydrogen telluride is the most toxic. Tel-lurium(IV) oxide and aqueous solutions of the salts of tellurous and telluric acids are also toxic. Only tellurium ( metallic ) is not toxic if it gets into an organism. 

The heterochalcogen cations S Se4 (x = 0-3) have been characterized in SO2 solution by Se NMR studies. X-ray structural analysis of (S3,oSei,o)2(Sb4F]7)(SbF6)3 have shown that the compound consists of two crystallographically independent Ss.oSei.o cations (for mixed Se/Te heterocyclic cations see Tellurium Inorganic Chemistry). 

Biomethylation. Methylation and methyl transfer are important reactions in the organic metabolism of organisms (Mudd, 1973) and it has been known for some time that dimethyl selenide, dimethyl telluride and di- and trimethyl arsine are biosynthetic products of the metabolism of inorganic compounds selenium, tellurium and arsenic, respectively, by microorganisms (Challenger, 1951). 

A review of spectrophotometric methods for tellurium determination has been presented [3]. The systems employing inorganic compounds forming coloured products, N-... 

Tellurium has two NMR-active nucleii Te and Te. Both have a nuclear spin of 1/2 see Tellurium Inorganic Chemistifj. Te is more abundant and has a better receptivity than Te. It has therefore found more general use in NMR spectroscopic characterization of tellurium-containing compounds. Some examples of the Te chemical shifts of diorganyl tellurides and ditellurides are shown in Table 1. The... 

Sihcon and boron bum ia fluorine forming siUcon tetrafluoride [7783-61-17, SiF, and boron trifluoride [7637-07-2] respectively. Selenium and tellurium form hexafluorides, whereas phosphoms forms tri- or pentafluorides. Fluorine reacts with the other halogens to form eight interhalogen compounds (see Fluorine compounds, inorganic-halogens). 

Inorganic salts/bases, slaked lime in, 15 65 Inorganic silicate coatings, 7 200 Inorganic surfaces, silylation of, 22 697-698, 701 Inorganic tellurium compounds, 24 417-422... 

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