Mercury telluride
| Names | |
|---|---|
| Systematic IUPAC name
Mercury telluride | |
| Other names
Mercuric telluride, mercury(II) telluride
| |
| Identifiers | |
3D model (JSmol)
|
|
| ChemSpider | |
| ECHA InfoCard | Lua error in Module:Wikidata at line 880: attempt to index field 'wikibase' (a nil value). Lua error in Module:Wikidata at line 880: attempt to index field 'wikibase' (a nil value).Lua error in Module:EditAtWikidata at line 29: attempt to index field 'wikibase' (a nil value). |
| EC Number |
|
| E number | Lua error in Module:Wikidata at line 880: attempt to index field 'wikibase' (a nil value). |
PubChem CID
|
|
CompTox Dashboard (EPA)
|
|
| |
| |
| Properties | |
| HgTe | |
| Molar mass | 328.19 g/mol |
| Appearance | near black cubic crystals |
| Density | 8.1 g/cm3 |
| Melting point | 670°C |
| Structure | |
| Sphalerite, cF8 | |
| F43m, No. 216 | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
| |
Mercury telluride (HgTe) is a binary chemical compound of mercury and tellurium. It is a semi-metal related to the II-VI group of semiconductor materials. Alternative names are mercuric telluride and mercury(II) telluride.
HgTe occurs in nature as the mineral form coloradoite.
Physical properties
[edit | edit source]All properties are at standard temperature and pressure unless stated otherwise. The lattice parameter is about 0.646 nm in the cubic crystalline form. The bulk modulus is about 42.1 GPa. The thermal expansion coefficient is about 5.2×10−6/K. The static and dynamic dielectric constants are 20.8 and 15.1, respectively. The thermal conductivity is low at 2.7 W·m2/(m·K). HgTe bonds are weak leading to low hardness values. The hardness is 2.7×107 kg/m2.[1][2][3]
Doping
[edit | edit source]N-type doping can be achieved with elements such as boron, aluminium, gallium, or indium. Iodine and iron will also dope n-type. HgTe is naturally p-type due to mercury vacancies. P-type doping is also achieved by introducing zinc, copper, silver, or gold.[1][2]
Topological insulation
[edit | edit source]
Mercury telluride was the first topological insulator discovered, in 2007. Topological insulators cannot support an electric current in the bulk, but electronic states confined to the surface can serve as charge carriers.[5]
Chemistry
[edit | edit source]HgTe bonds are weak. Their enthalpy of formation, around −32kJ/mol, is less than a third of the value for the related compound cadmium telluride. HgTe is easily etched by acids, such as hydrobromic acid.[1][2]
Growth
[edit | edit source]Bulk growth is from a mercury and tellurium melt in the presence of a high mercury vapour pressure. HgTe can also be grown epitaxially, for example, by sputtering or by metalorganic vapour phase epitaxy.[1][2]
Nanoparticles of mercury telluride can be obtained via cation exchange from cadmium telluride nanoplatelets.[6]
See also
[edit | edit source]References
[edit | edit source]- ^ a b c d Brice, J. and Capper, P. (eds.) (1987) Properties of mercury cadmium telluride, EMIS datareview, INSPEC, IEE, London, UK.
- ^ a b c d Capper, P. (ed.) (1994) Properties of Narrow-Gap Cadmium-Based Compounds. INSPEC, IEE, London, UK. Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
- ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
External links
[edit | edit source]- Thermophysical properties database[permanent dead link] at Germany's Chemistry Information Centre, Berlin