Mercury selenide
| Mercury(II) selenide | |
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Mercury selenide |
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| Identifiers | |
| CAS number | 20601-83-6  |
| PubChem | 88609 |
| Properties | |
| Molecular formula | HgSe |
| Molar mass | 279.55 g/mol |
| Appearance | grey-black solid |
| Density | 8.3 g/cm3 |
| Melting point |
997 °C, 1270 K, 1826 °F |
| Solubility in water | insoluble |
| Structure | |
| Crystal structure | sphalerite |
| Thermochemistry | |
| Std enthalpy of formation ΔfH |
247 kJ/mol |
| Specific heat capacity, C | 178 J kg−1 K−1 |
| Hazards | |
| EU Index | 080-002-00-6 |
| EU classification | Very toxic (T+) Dangerous for the environment (N) |
| R-phrases | R26/27/28, R33, R50/53 |
| S-phrases | (S1/2), S13, S28, S45, S60, S61 |
| Flash point | Non-flammable |
| Related compounds | |
| Other anions | Mercury oxide Mercury sulfide Mercury telluride |
| Other cations | Zinc selenide Cadmium selenide |
 (verify) (what is:  / ?)Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) |
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| Infobox references | |
Mercury selenide (HgSe) is a chemical compound of mercury and selenium. It is a grey-black crystalline solid semi-metal with a sphalerite structure. The lattice constant is 0.608 nm.
Mercury selenide can also refer to the following chemical compounds: HgSe2 and HgSe8. HgSe is strictly mercury(II) selenide.
HgSe occurs naturally as the mineral Tiemannite.
Along with other II-VI compounds, colloidal nanocrystals of HgSe can be formed.
Applications
- Selenium is used in filters in some steel plants to remove mercury from exhaust gases. The solid product formed is HgSe.
- HgSe can be used as an ohmic contact to wide-gap II-VI semiconductors such as zinc selenide or zinc oxide.
Toxicity
HgSe is non-toxic so long as it is not ingested due to its insolubility. Toxic hydrogen selenide fumes can be evolved on exposure to acids. HgSe is a relatively stable compound which might mean that it is less toxic than elemental mercury or many organometallic mercury compounds. Selenium's ability to complex with mercury has been proposed as a reason for the lack of mercury toxicity in deep sea fish despite high mercury levels.[1]
References
- ^ Watanabe, C. (2002). "Modification of Mercury Toxicity by Selenium: Practical Importanc?". The Tohoku Journal of Experimental Medicine 196 (2): 71–77. doi:10.1620/tjem.196.71. PMID 12498318.
- Nelson, D.; Broerman, J.; Paxhia, E.; Whitsett, C. (1969). "Resonant Phonon Scattering in Mercury Selenide". Physical Review Letters 22 (17): 884. doi:10.1103/PhysRevLett.22.884.
- Jayaraman, A.; Klement, W.; Kennedy, G. (1963). "Melting and Polymorphic Transitions for Some Group II-VI Compounds at High Pressures". Physical Review 130 (6): 2277. doi:10.1103/PhysRev.130.2277.
- Gawlik, K. -U.; Kipp, L.; Skibowski, M.; Orłowski, N.; Manzke, R. (1997). "HgSe: Metal or Semiconductor?". Physical Review Letters 78 (16): 3165. doi:10.1103/PhysRevLett.78.3165. .
- Kumazaki, K. (1990). "Dielectric properties of narrow-gap semiconductors". Journal of Crystal Growth 101: 687–690. doi:10.1016/0022-0248(90)91059-Y.
- SNV (1991) Guidelines on measures and methods for heavy metal emissions control. Solna, The Swedish Environmental Protection Agency – Naturvårdsverket.
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