Gallium , crystal structure

The gallium and indium complexes of novel bis(thiosemicarbazones) have been investigated.71-73 Initial publications indicated a more complex stoichiometry where X-ray crystal structures suggested either dinuclear or trinuclear complexes. Whereas these complexes are quite interesting, they are less likely to result in useful nuclear medicine radiopharmaceuticals. The bis(thiosemi-carbazones) are quite useful as ligands for copper, and are discussed in more detail vide infra). 

Silicon is the most popular material for photovoltaic (PV) power. Another material is gallium arsenide (GaAs), which is a compound semiconductor. GaAs has a crystal structure similar to that of silicon, but it consists of alternating gallium and arsenic atoms. It is well suited for PV applications since it has a high light absorption coefficient and only a thin layer of material is required, which reduces the cost. 

Alkane elimination was also observed upon heating of the adducts RaGa NH2-NR R" [4 to 7, Eq. (2)] in boiling toluene, which gave the hydrazides 15 to 18 in excellent yields [Eq. (6)] [17]. One compound (17) was characterized by a crystal structure determination. Similar gallium hydrazides were obtained directly at room temperature without the isolation of stable adducts when the phenylhydrazine derivatives H2N-N(H)CeH5 [18] and H2N-N(C6Hs)2 [17] were employed. The products (15 to 18) form dimers... 

Since ionic radii and valences of iron and chromium ions are similar to gallium ion, substitution of these cations with gallium ion may result in powders with similar crystal structure and properties to LSGM. Moreover, LaFe03- and LaCr03-based oxides are candidate cathode and anode materials for SOFC, respectively. 

In analogy to the synthesis of the aluminum compounds XXXVI and XXXVII the closo gallium carboranes XLIII and XLIV have been prepared (141), but crystal structures are not yet available. From NMR spectroscopic data it appears that they possess icosahedral structures as shown in Fig. 9. 

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