Thallium -oxide

Thallium( ) oxide, TI2O. Black powder formed by heating TIOH, gives T1(I) salts with acids. 

Mixtures of the oxide with sulfur or antimony trisulfide explode on grinding in a mortar. Dry hydrogen sulfide ignites, and sometimes feebly explodes, over thallium oxide. 

Bhattacharya, R. N. Feldmann, M. Larbalestier, D. Blaugher, R. D. 2001. Electrodeposition process for the preparation of superconducting thallium oxide films. IEEE Trans. Appl. Supercond. 11 3102-3105. 

Thallium metal, 24 627—629 Thallium nitrates, 24 633 Thallium organometallics, 24 633—635 Thallium oxides, 24 632—633 Thallium poisonings, 24 637, 638-639 Thallium stress test, 24 629 Thallium sulfates, 24 628, 633 Thaumatin, 72 43, 24 241-242 Thaumatin II, 24 242 Theaspiranes, 24 572 Thebaine, 2 89 Thenardite, 22 863, 5 785t Thenoyltrifluoroacetone molecular formula, 5 712t Theobroma cacao, 6 350 Theobromine, 2 105-106... 

Friedel-Crafts reactions involving electrophilic substitution of aromatic compounds have been reported on solid base catalysts such as thallium oxide and MgO. The rates of benzylation of toluene by benzyl chloride over MgO nanocrystals were found to be of the order CP-MgO > CM-MgO > AP-MgO.56 An important observation in the study was that x-ray diffraction of the spent catalyst... 

Elemental thallium metal is rare in nature mainly because it oxidizes if exposed to air (oxygen) and water vapor, forming thallium oxide, a black powder. Although some compounds of thallium are both toxic and carcinogenic, they have some uses in the field of medicine. Some compounds have the ability to alter their electrical conductivity when exposed to infrared light. 

Thallium oxide is used in manufacturing high coefficient of refraction optical glass (thallium flint glass). Also, the oxide is used to make synthetic gems. 

Thallium oxide can he made hy heating T1 metal in air or oxygen. The hrown-black thallic oxide, TI2O3, that may also form begins to lose oxygen at about 100°C converting to thallium oxide, TbO. 

Thallium oxide also can he prepared hy thermal dissociation of thallium hydroxide, TlOH or thallium carbonate, TI2CO3. Thallium oxide dissolves in water forming thallous hydroxide, TlOH. It reacts with carbon dioxide to form thallous carbonate, TI2CO3. 

Thallium oxide slowly oxidizes to thallic oxide, TI2O3 on exposure to air, gradually becoming insoluble in aqueous solution. 

Elemental composition T1 96.23%, 0 3.77%. ThaUium may be measured by various instrumental methods on an aqueous or acid solution of the metal oxide. Also, the compound can be identified by its physical and x-ray properties. Thallic oxide reverts to thallium oxide on heating above 100°C. 

Crystal growth of these compounds is complicated by the high volatility of thallium oxides and thallium-containing compounds at elevated temperatures and the toxicity of thallium. Also, the similarity in structures leads to problems controlling phase purity and samples which appear to be single crystals based on their morphology can be shown to be complicated intergrowths by X-ray diffraction studies. 

Thallium(III) oxide is a degenerate n-type semiconductor (see Semiconductors) with a Band Gap of 1.4 eV, and it shows electronic and optical properties, which make it useful in applications such as solar cells and electrical contacts. The interest in thallium oxide has been further stimulated by the discovery that the system Tl-Ca-Ba-Cu-O represents a... 

SYNS DITHALLIUM TRIOXIDE RCRA WASTE NUMBER P113 THALUC OXIDE THALLIUM OXIDE D THALLIUM(3+) OXIDE THALLIUM PEROXIDE THALLIUM SESQUIOXIDE... 

Although the of Tl Ba2Ca iCu 02 +, +2 is very high, the research for practical applications is not so active. This is because of not only the high vapor pressure of thallium oxide when tiring the sample to synthesize Tl, Ba2Ca iCu 02 + +2, but also because of the toxicity of thallium. 

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