Mercury telluride

Mercury telluride
Mercury telluride
Identifiers
CAS number 12068-90-5 YesY
Properties
Molecular formula HgTe
Molar mass 329.18 g/mol
Appearance near black cubic crystals
Density 8.1 g/cm3
Structure
Crystal structure Sphalerite, cF8
Space group F-43m, No. 216
 YesY telluride (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

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.


Contents

Properties

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. Static dielectric constant 20.8, dynamic dielectric constant 15.1. Thermal conductivity is low at 2.7W·m2/m·K. HgTe bonds are weak leading to low hardness values. Hardness 2.7×107 kg/m2.

Doping

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.

Chemistry

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.

Growth

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.

Unique physical properties

Recently it was shown both theoretically and experimentally, that mercury-telluride quantum well shows a unique new state of matter—the "topological insulator". In this phase, while the bulk is an insulator, current can be carried by electronic states confined close to the sample edges. Unlike the quantum hall effect, here no magnetic field is required to create this unique behavior. In addition, oppositely directed edge states carry opposite spin projections.

See also

Related compounds

References

  • Properties of mercury cadmium telluride, Ed. J. Brice and P. Capper, EMIS datareview, (INSPEC, IEE, London, UK, 1987).
  • Properties of Narrow-Gap Cadmium-Based Compounds Ed. P. Capper (INSPEC, IEE, London, UK, 1994) ISBN 0-85296-880-9
  • Tellurium and Tellurides, D. M. Chizhikov and V. P. Shchastlivyi, 1966, Nauka Publishing, Moscow
  • Mercury selenide stoichiometry and phase relations in the mercury-selenium system, N. Z. Boctor and G. Kullerud, Journal of Solid State Chemistry Vol. 62, pp. 177–183 (1986) doi:10.1016/0022-4596(86)90229-X
  • Total-energy study of the equation of state of HgTe and HgSe, Z. W. Lu, David Singh, and Henry Krakauer, Phys. Rev. B vol. 39, pp. 10154 (1989).
  • Quantum Spin Hall Insulator State in HgTe Quantum Wells, M. Konig et al., Science 318 766 (2007).

External links


Wikimedia Foundation. 2010.

Игры ⚽ Поможем решить контрольную работу

Look at other dictionaries:

  • Mercury zinc telluride — (HgZnTe, MZT) is a telluride of mercury and zinc, an alloy of mercury telluride and zinc telluride. It is a narrow gap semiconductor material. Mercury zinc telluride is used in infrared detectors and arrays for infrared imaging and infrared… …   Wikipedia

  • Mercury(II) telluride — 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… …   Wikipedia

  • Mercury selenide — Mercury(II) selenide IUPAC name Mercury selenide …   Wikipedia

  • Mercury(II) oxide — Mercury(II) oxide …   Wikipedia

  • Mercury sulfide — Mercury sulfide …   Wikipedia

  • Mercury cadmium telluride — HgCdTe or mercury cadmium telluride (also cadmium mercury telluride, MCT or CMT) is an alloy of CdTe and HgTe and is sometimes claimed to be the third semiconductor of technological importance after silicon and gallium(III) arsenide. The amount… …   Wikipedia

  • Mercury(II) cadmium(II) telluride — HgCdTe or mercury cadmium telluride (also cadmium mercury telluride, MCT or CMT) is an alloy of CdTe and HgTe and is sometimes claimed to be the third semiconductor of technological importance after silicon and gallium(III) arsenide. The amount… …   Wikipedia

  • Mercury(II) selenide — Chembox new Name = Mercury(II) selenide ImageFile = Mercury(II) selenide unit cell 3D ionic.png ImageName = Mercury(II) selenide unit cell IUPACName = OtherNames = Section1 = Chembox Identifiers SMILES = CASNo = 20601 83 6 RTECS = Section2 =… …   Wikipedia

  • Mercury (element) — gold ← mercury → thallium Cd ↑ Hg ↓ Cn …   Wikipedia

  • Cadmium telluride — Other names Irtran 6 Identifiers …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”