Mercury(II) selenide

Names
IUPAC name Mercury selenide
Identifiers
CAS Number	20601-83-6 Y
3D model (JSmol)	Interactive image
ECHA InfoCard	100.039.903
EC Number	243-910-5
PubChem CID	88609
CompTox Dashboard (EPA)	DTXSID8066630
InChI InChI=1S/Hg.Se Key: YQMLDSWXEQOSPP-UHFFFAOYSA-N InChI=1S/Hg.Se
SMILES [Se]=[Hg]
Properties
Chemical formula	HgSe
Molar mass	279.55 g/mol
Appearance	grey-black solid
Odor	odorless
Density	8.266 g/cm3
Melting point	1,000 °C; 1,830 °F; 1,270 K
Solubility in water	insoluble
Structure
Crystal structure	sphalerite
Thermochemistry
Heat capacity (C)	178 J kg−1 K−1
Std enthalpy of formation (ΔfH⦵298)	247 kJ/mol
Hazards
GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H300, H310, H330, H373, H410
Precautionary statements	P260, P262, P264, P270, P271, P273, P280, P284, P301+P310, P302+P350, P304+P340, P310, P314, P320, P321, P322, P330, P361, P363, P391, P403+P233, P405, P501
NFPA 704 (fire diamond)	3 0 1
Flash point	Non-flammable
Related compounds
Other anions	Mercury oxide Mercury sulfide Mercury telluride
Other cations	Zinc selenide Cadmium selenide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Mercury selenide (HgSe; sometimes mercury(II) selenide) 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.

HgSe occurs naturally as the mineral Tiemannite, and is a component of the "intimate mixture" of HgSe and Se known as HgSe₂.^[1]

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 as 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.^[2]