Indium complexes oxides

Coordination Compounds. A large number of indium complexes with nitrogen ligands have been isolated, particularly where Ir is in the +3 oxidation state. Examples of ammine complexes include pr(NH3)3] " [24669-15-6], prCl(NH3)] " [29589-09-1], and / j -pr(03SCF3)2(en)2]" [90065-94-4], Compounds of A/-heterocychc ligands include trans- [xCX py)][ [24952-67-8], Pr(bipy)3] " [16788-86-6], and an unusual C-metalated bipyridine complex, Pr(bipy)2(C, N-bipy)] [87137-18-6]. Isolation of this latter complex produced some confusion regarding the chemical and physical properties of Pr(bipy)3]3+ (167). 

Very recently a new kind of electrocatalyst has been propounded using the dinuclear quinone-containing complex of ruthenium (25).492,493 Controlled-potential electrolysis of the complex at 1.70 V vs. Ag AgCl in H20 + CF3CH2OH evolves dioxygen with a current efficiency of 91% (21 turnovers). The turnover number of 02 evolution increases up to 33,500 when the electrolysis is carried out in water (pH 4.0) with an indium-tin oxide(ITO) electrode to which the complex is bound. It has been suggested that the four-electron oxidation of water is achieved by redox reactions of not only the two Run/Ruin couples, but also the two semiquinone/quinone couples of the molecule. 

The chemistry of indium complexes of aU types in metal oxidation states lower than +3 has been comprehensively reviewed. Few lower oxidation state mononuclear amido complexes of indium are well characterized, however, and no structure has been reported for an In(I) amide. The compound In N(SiMe3)2 n. which is unstable, " has been characterized NMR spectroscopy but its structure is unknown. The structures of several In(I) complexes, related to amides but outside our current scope, have been described. Like its aluminium and gallium counterparts, the p-diketuninate derivative [ In N(Dipp)C(Me) 2CH] has been characterized, as has the closely related species [ In N(Dipp)C(CF3) 2CH]. ° These feature V-shaped, two-coordination at the metal. The less bulky [(In N(Mes)C(Me) 2-CH)2] ° and 15-2.6-.Vlc,)( (Me) i are dimeric with long In In bonds of... 

In the report that described the synthesis of 108 (777), Whitmire also observed that the reaction between NaBi03 and methanolic [Fe(CO)s] in the presence of hydroxide afforded the trianionic species [Bi Fe(CO)4 4]3, 110, which was subsequently characterized by X-ray crystallography (775). Cluster 110 contains a central bismuth atom tetrahedrally coordinated by four Fe(CO)4 fragments and is isoelectronic with the anionic tetracobalt-indium complex, 27, and the neutral tetracobalt-germanium, - tin, and -lead complexes, 68, 71, and 72. Oxidation of 110 affords 108 (777), while acidification (772) yields the hydride-containing cluster [BiFe3(CO)9(/i-H)3], 111, which also contains a tetrahedral BiFe3 core. Johnson and Lewis (114) have... 

The chemical properties of indium are typical of those of Group 13 of the Periodic Table. Most of indium s oxides, salts, and compounds involve the +3 oxidation state (e.g., In203, In[N03]3> and InCl3) many of these compounds are electron-pair acceptors, forming addition compounds with donor molecules (e.g., InBr3 py, py = pyridine). Neutral, cationic, and anionic complexes are also known. Several interesting compounds are derived from the +1 and +2 oxidation states of the element. 

Most of the reported intermetallic indium complexes are those where the indium is in low oxidation state and are hence discussed in Section 8. Examples where the indium metal center is in higher oxidation states are given below. The intermetallic (dialkylaminomethyl)-phenylindium derivative is synthesized via metathesis as outlined in Scheme 17. The compound exists as a distorted trigonal bipyramid since the N In N angle of 143.1(2) falls considerably short of an ideal trigonal bipyramid (180°). 

Coupled techniques have increased in popularity in recent years. Electrochemical techniques can be coupled to another characterization method to provide unique information. Many electrochemical techniques lend themselves well to coupling with other electrochemical or nonelectrochemical techniques. With these methods, cell design is often complex to allow simultaneous execution of both techniques. For example, optically transparent indium tin oxide is used as the working electrode with an optically transparent mesh electrode to allow for simultaneous electrochemical conversion and electronic absorption spectroscopy. For some techniques the sample is electrolyzed and then transferred under inert atmosphere for analysis. 

Silicon electrodes can also be stabilized by depositing a layer of compounds of oxides and silicides such as Ru02, molybdenum dinitrogen complexes, manganese oxide, indium-tin oxide, " aluminum oxide and aluminosilicate. In contrast to the noble metals, deposition of islands of Pb and Cd tends to inhibit hydrogen evolution in H2SO4 solution. ... 

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