Thallous oxide

Thallium forms all its compounds in two valence states, +1 (thallous) and +3 (thallic). The metal oxidizes slowly in air at ambient temperature but rapidly on heating, forming thallous oxide, TI2O. This oxide oxidizes further on heating to form thallic oxide, TI2O3. When exposed to air at ambient temperatures for several days thallium forms a heavy oxide crust. 

Oxides and Hydroxides. Thallous oxide is most readily obtained by dehydration of TlOH in high vacuum at 50°C. It is black, crystalline, and hygroscopic. It reacts with water to form the hydroxide and dissolves in ethanol to yield the ethoxide (9). 

Uses. Thallium compounds have limited use in industrial applications. The use of thallous sulfate in rodenticides and insecticides has been replaced by other compounds less harm fill to animals (see Insect control technology Pesticides). Thallium sulfide has been used in photoelectric cells (see Photovoltaic cells). A thallium bromide—thallium iodide mixture is used to transmit infrared radiation for signal systems. Thallous oxide is used in the manufacture of glass (qv) that has a high coefficient of refraction. Thallium formate—malonate aqueous solutions (Cletici s solution) have been used in mineral separations. Many thallium compounds have been used as reagents in oiganic synthesis in research laboratories. 

The thallous azide was subjected to an exposure. 5,4 x 109 R and was reduced to a form of thallous oxide according to IR spectra... 

The hydroxide, Tl(OH), forms yellow crystalline needles, and may be formed by dissolving thallous oxide in water or by adding baryta to thallous... 

Cubicciotti, D. (1970). The thermodynamics of vaporization of thallous oxide. High Temp. Sci., 2. 213-220. 

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