Technetium binary

Most chemical properties of technetium are similar to those of rhenium. The metal exhibits several oxidation states, the most stable being the hep-tavalent, Tc +. The metal forms two oxides the black dioxide Tc02 and the heptoxide TC2O7. At ambient temperature in the presence of moisture, a thin layer of dioxide, Tc02, covers the metal surface. The metal burns in fluorine to form two fluorides, the penta- and hexafluorides, TcFs and TcFe. Binary compounds also are obtained with other nonmetaUic elements. It combines with sulfur and carbon at high temperatures forming technetium disulfide and carbide, TcS2 and TcC, respectively. 

Binary metal carbonyl complexes, with technetium, 5, 835 Binary technetium isocyanides, preparation and properties,... 

No binary xanthate structures of manganese, technetium, or rhenium have been reported. Indeed, there are relatively few crystal structures known with only a single manganese structure (two polymorphs), two phosphine adducts of technetium and three structures containing rhenium, two of which are dinuclear. 

Group 7 (Mn, Tc, Re). No binary compounds are formed with manganese, and no homogeneous product could be prepared. Technetium reacts with W, forming a solid solution and a a-phase (WTcs). Timgsten-technetium alloys are of practical interest as superconductors. 

Stable binary metal carbonyls, negatively charged or uncharged, exist for all the elements of the 3d, 4d, and 5d transition series from CSroup 4 to Group 10, with the exception of palladium. As shown in Table 1, some of the elements (Ti, Zr, Hf, Nb, Ta, and Pt) have anionic carbonylmetalates only and no stable uncharged derivatives have so far been reported. Of the known metal carbonyls, only those of Group 6, Group 7 (with the exclusion of technetium), iron, ruthenium, cobalt and nickel have been used much in catalytic processes. 

Complex-formation and redox reactions have so far been the most frequently used for the determination of both metals and nonmetals (Table 3). A variety of transition metal ions have been thus determined including such common elements as iron, copper, and calcium and rare earths as well as technetium and europium. Common nonmetals such as nitrogen anions and phosphate, bromide, and sulfur anions have also been determined this way. However, the most important applications of noncatalytic reactions in inorganic analysis are the simultaneous determinations of metal ions. As can be seen in Table 4, a wide variety of binary mixtures and some ternary and even... 

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