Gallium(II) telluride

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Gallium(II) telluride
Gallium(II) telluride
Identifiers
CAS number 12024-14-5
Properties
Molecular formula GaTe
Molar mass 197.32 g/mol
Appearance black pieces
Density 5.44 g/cm3, solid
Melting point 824°C
Structure
Crystal structure hexagonal, hP8
Space group P63/mmc, No. 194
Hazards
EU classification not listed
NFPA 704
Flammability code 0: Will not burn. E.g., water Health code 4: Very short exposure could cause death or major residual injury. E.g., VX gas Reactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogen Special hazards (white): no codeNFPA 704 four-colored diamond
Related compounds
Other anions gallium(II) oxide, gallium(II) sulfide, gallium monoselenide
Other cations zinc(II) telluride, germanium(II) telluride, indium(II) telluride
Related compounds gallium(III) telluride
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
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Infobox references

Gallium(II) telluride, GaTe, is a chemical compound of gallium and tellurium. There is research interest in the structure and electronic properties of GaTe because of the possibility that it, or related compounds, may have applications in the electronics industry. Gallium telluride can be made by reacting the elements or by metal organic vapour deposition (MOCVD).[1] . GaTe produced from the elements has a monoclinic crystal structure. Each gallium atom is tetrahedrally coordinated by 3 tellurium and one gallium atom. The gallium-gallium bond length in the Ga2 unit is 2.43 Angstrom. The structure consists of layers and can be formulated as Ga24+ 2Te2−.[2] The bonding within the layers is ionic-covalent and between the layers is predominantly van der Waals. GaTe is classified as a layered semiconductor (like GaSe and InSe which have similar structures). It is a direct band gap semiconductor with an energy of 1.65eV at room temperature.[3] A hexagonal form can be produced by low pressure metal organic vapour deposition (MOCVD) from alkyl gallium telluride cubanes e.g. from (t-butylGa( μ3-Te))4. These cubanes are so-called because they have a structure related to C8H8, cubane. The core consists of a cube of eight atoms, four gallium, and four tellurium atoms. Each gallium has an attached t-butyl group and three adjacent tellurium atoms and each tellurium has three adjacent gallium atoms. The hexagonal form, which is closely related to the monoclinic form, containing Ga24+ units, converts to the monoclinic form when annealed at 500°C.[1]

References[edit]

Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 0080379419. 

  1. ^ a b Chemical Vapor Deposition of Hexagonal Gallium Selenide and Telluride Films from Cubane Precursors: Understanding the Envelope of Molecular Control E G. Gillan and A R. Barron Chem. Mater., 9 (12), 3037 -3048, 1997.
  2. ^ Monotellurure de gallium, GaTe, Julien-Pouzol M., Jaulmes S.,Guittard M.,Alapini F., Acta Crystallographica B. Vol. 35, no. 12, pp. 2848-2851. 15 Dec. 1979 doi:10.1107/S0567740879010803
  3. ^ Anharmonicity in GaTe layered crystals, A. Aydinli, N. M. Gasanly, A. Uka, H. Efeoglu, Cryst. Res. Technol. 37 (2002) 12 1303–1309