Compounds of Gallium

An alternative to gallium vapour is an organometallic compound of gallium. One preparation reacts trimethyl gallium (Ga (0113)3) with the highly volatile (although toxic) arsine (AsHs). 

CH3)3N GaH3, (CH3)3P GaH3 [15279-03-5], and (CH3)2N GaH2 [32342-80-6], These are used for the preparation of other oiganic compounds of gallium. 

Relatively few organic compounds of gallium have been described, indicating that gallium chemistry is still in a stage where most of the progress is achieved by synthetic work rather than through study of reactions and physical properties. 

The chemistry of gallium is very similar to that of aluminum, its congener. Compounds of gallium almost always have a +3 oxidation state. While a few compounds with a +1 and +2 state have been postulated, these are controversial. 

Many other compounds have been added to Cr/silica and claimed to tailor some polymer property. The list includes compounds of gallium [594], boron [548], molybdenum [615], and many others. The response (if any) of Cr/silica catalysts to these other modifiers has sometimes been weak at best, or the claims simply could not be confirmed under industrial conditions. For example, claims made in the literature [615] for molybdenum as a modifier could not be confirmed in our laboratory. 

Increasing prominence of the lower oxidation state. When a group exhibits more than one oxidation state, the lower state becomes more prominent going down the group. In Group 3A(13), for instance, all members exhibit the +3 state, but the +1 state first appears with some compounds of gallium and becomes the only important state of thallium. 

Triethylgallium monoetherate, Et3Ga-(Et20), the first reported organometaiiic compound of gallium, was isolated from reaction of ethylmagnesium bromide with gallium bromide in 1932 (equation 1). ... 

THE BRILLIANT COLORS OF light-emitting diodes (LEDs) arise from the composition of the materials from which they are made. The LEDs shown here are compounds of gallium and aluminum mixed with nitrogen, phosphorus, and arsenic. GaN, GaP, and GaAs can make solid solutions with each other and with AIN,... 

The stoichiometric compound of gallium and oxygen, Ga203, exists in a wide variety of polymorphic phases, including a, p, y, b, e, and 0 phases that so far have heen identified using powder X-ray diffraction (XRD) [72]. The polymorphs a and p are usually prepared at ambient pressure from thermal decomposition of the nitrate (Ga(N03)3), or via sol-gel synthesis routes followed hy dehydration and recrystal-lization of the gel (Figure 3.3 adapted from [72]). 

State first appears with some compounds of gallium and becomes the only important state of thallium. 

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