Names | |
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IUPAC name Chromium(2+) selenide | |
Identifiers | |
3D model (JSmol) | |
ECHA InfoCard | 100.031.805 |
EC Number |
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PubChem CID | |
CompTox Dashboard (EPA) | |
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Properties | |
CrSe | |
Molar mass | 130.96 g/mol |
Appearance | white to pale yellow crystalline powder |
Density | 6.74 g/cm3 |
Melting point | ~1500 °C |
insoluble | |
Structure [1] | |
NiAs type (hexagonal) | |
P63/mmc, No. 194 | |
a = 371 pm, c = 603 pm | |
Hazards | |
NFPA 704 (fire diamond) | |
NIOSH (US health exposure limits): | |
PEL (Permissible) | TWA 1 mg/m3 [2] |
REL (Recommended) | TWA 0.5 mg/m3 [2] |
IDLH (Immediate danger) | 250 mg/m3 [2] |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Chromium(II) selenide is an inorganic compound with the chemical formula CrSe. It crystalizes in a hexagonal structure with space group P63/mmc. [3] It is one of many related Chromium-Selenium phases, including Cr7Se8, Cr3Se4, Cr0.68Se, Cr2Se3, and Cr5Se8. [3] The compound has been described as an antiferromagnet, but its inverse magnetic susceptibility does not match the behavior expected for an antiferromagnet according to the Curie–Weiss law. [1] One suggestion was that the Néel temperature is at 320 K, as the temperature where the compound has maximum specific heat. [4] When synthesized as single atomic layer, CrSe is ferromagnetic, with a Curie Temperature of around 280 K. [5]
Chromium(III) chloride (also called chromic chloride) is an inorganic chemical compound with the chemical formula CrCl3. It forms several hydrates with the formula CrCl3·nH2O, among which are hydrates where n can be 5 (chromium(III) chloride pentahydrate CrCl3·5H2O) or 6 (chromium(III) chloride hexahydrate CrCl3·6H2O). The anhydrous compound with the formula CrCl3 are violet crystals, while the most common form of the chromium(III) chloride are the dark green crystals of hexahydrate, CrCl3·6H2O. Chromium chlorides find use as catalysts and as precursors to dyes for wool.
Cadmium selenide is an inorganic compound with the formula CdSe. It is a black to red-black solid that is classified as a II-VI semiconductor of the n-type. It is a pigment but applications are declining because of environmental concerns
Hydrogen selenide is an inorganic compound with the formula H2Se. This hydrogen chalcogenide is the simplest and most commonly encountered hydride of selenium. H2Se is a colorless, flammable gas under standard conditions. It is the most toxic selenium compound with an exposure limit of 0.05 ppm over an 8-hour period. Even at extremely low concentrations, this compound has a very irritating smell resembling that of decayed horseradish or 'leaking gas', but smells of rotten eggs at higher concentrations.
Chromium hexacarbonyl (IUPAC name: hexacarbonylchromium) is a chromium(0) organometallic compound with the formula Cr(CO)6. It is homoleptic complex, which means that all the ligands are identical. It is a white, air-stable solid with a high vapor pressure.
Selenium dioxide is the chemical compound with the formula SeO2. This colorless solid is one of the most frequently encountered compounds of selenium.
Copper(II) fluoride is an inorganic compound with the chemical formula CuF2. The anhydrous form is a white, ionic, crystalline, hygroscopic solid with a distorted rutile-type crystal structure, similar to other fluorides of chemical formulae MF2 (where M is a metal). The dihydrate, CuF2·2H2O, is blue in colour.
Chromium dioxide or chromium(IV) oxide is an inorganic compound with the formula CrO2. It is a black synthetic magnetic solid. It once was widely used in magnetic tape emulsion. With the increasing popularity of CDs and DVDs, the use of chromium(IV) oxide has declined. However, it is still used in data tape applications for enterprise-class storage systems. It is still considered by many oxide and tape manufacturers to have been one of the best magnetic recording particulates ever invented.
The term magnetic structure of a material pertains to the ordered arrangement of magnetic spins, typically within an ordered crystallographic lattice. Its study is a branch of solid-state physics.
Selenium monochloride or diselenium dichloride is an inorganic compound with the formula Se2Cl2. Although it is incorrectly called selenium monochloride, one of the correct names might be diselenium dichloride or dichlorodiselane. It is a reddish-brown, oily liquid that hydrolyses slowly. It exists in chemical equilibrium with SeCl2, SeCl4, chlorine, and elemental selenium. Diselenium dichloride is mainly used as a reagent for the synthesis of Se-containing compounds.
Chromium hydrides are compounds of chromium and hydrogen, and possibly other elements. Intermetallic compounds with not-quite-stoichometric quantities of hydrogen exist, as well as highly reactive molecules. When present at low concentrations, hydrogen and certain other elements alloyed with chromium act as softening agents that enables the movement of dislocations that otherwise not occur in the crystal lattices of chromium atoms.
Chromium pentafluoride is the inorganic compound with the chemical formula CrF5. It is a red volatile solid that melts at 34 °C. It is the highest known chromium fluoride, since the hypothetical chromium hexafluoride has not yet been synthesized.
Chromium(III) boride, also known as chromium monoboride (CrB), is an inorganic compound with the chemical formula CrB. It is one of the six stable binary borides of chromium, which also include Cr2B, Cr5B3, Cr3B4, CrB2, and CrB4. Like many other transition metal borides, it is extremely hard (21-23 GPa), has high strength (690 MPa bending strength), conducts heat and electricity as well as many metallic alloys, and has a high melting point (~2100 °C). Unlike pure chromium, CrB is known to be a paramagnetic, with a magnetic susceptibility that is only weakly dependent on temperature. Due to these properties, among others, CrB has been considered as a candidate material for wear resistant coatings and high-temperature diffusion barriers.
Phosphorus selenides are a relatively obscure group of compounds. There have been some studies of the phosphorus - selenium phase diagram and the glassy amorphous phases are reported. The compounds that have been reported are shown below. While some of phosphorus selenides are similar to their sulfide analogues, there are some new forms, molecular P2Se5 and the polymeric catena-[P4Se4]x. There is also some doubt about the existence of molecular P4Se10.
Chromium(III) phosphate describes inorganic compounds with the chemical formula CrPO4.(H2O)n, where n = 0, 4, or 6. All are deeply colored solids. Anhydrous CrPO4 is green. The hexahydrate CrPO4•6H2O is violet.
Oxyselenides are a group of chemical compounds that contain oxygen and selenium atoms. Oxyselenides can form a wide range of structures in compounds containing various transition metals, and thus can exhibit a wide range of properties. Most importantly, oxyselenides have a wide range of thermal conductivity, which can be controlled with changes in temperature in order to adjust their thermoelectric performance. Current research on oxyselenides indicates their potential for significant application in electronic materials.
Platinum diselenide is a transition metal dichalcogenide with the formula PtSe2. It is a layered substance that can be split into layers down to three atoms thick. PtSe2 can behave as a metalloid or as a semiconductor depending on the thickness.
Borate sulfides are chemical mixed anion compounds that contain any kind of borate and sulfide ions. They are distinct from thioborates in which sulfur atoms replace oxygen in borates. There are also analogous borate selenides, with selenium ions instead of sulfur.
Plutonium selenide is a binary inorganic compound of plutonium and selenium with the chemical formula PuSe. The compound forms black crystals and does not dissolve in water.
Corundum is the name for a structure prototype in inorganic solids, derived from the namesake polymorph of aluminum oxide (α-Al2O3). Other compounds, especially among the inorganic solids, exist in corundum structure, either in ambient or other conditions. Corundum structures are associated with metal-insulator transition, ferroelectricity, polar magnetism, and magnetoelectric effects.
Europium monoselenide is a binary inorganic compound of europium and selenium with the chemical formula EuSe. The compound forms black crystals.