Glowing powder mixture of promethium(III) chloride and zinc sulfide | |
Crystal structure | |
Names | |
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Other names Promethium chloride; Promethium trichloride | |
Identifiers | |
3D model (JSmol) | |
ChemSpider | |
ECHA InfoCard | 100.034.004 |
EC Number |
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PubChem CID | |
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Properties | |
Cl3Pm | |
Molar mass | 251 g·mol−1 |
Density | 4.19 g/cm3 (calc., XRD) [1] |
Melting point | 655 °C (1,211 °F; 928 K) [2] |
Structure | |
Trigonal, hP8 | |
P63/m, No. 176 [1] | |
Related compounds | |
Other anions | Promethium(III) oxide |
Other cations | Neodymium(III) chloride, Samarium(III) chloride |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Promethium(III) chloride is a chemical compound of promethium and chlorine with the formula PmCl3. It is an ionic, water soluble, crystalline salt that glows in the dark with a pale blue or green light due to promethium's intense radioactivity.
Promethium(III) chloride is obtained from promethium(III) oxide by heating it in a stream of dry HCl at 580 °C. [3]
Promethium(III) chloride is a purple solid with a melting point of 655 °C. [4] It crystallizes in the hexagonal crystal system (NdCl3 type) with the lattice parameters a = 739 pm and c = 421 pm with two formula units per unit cell and thus a calculated density of 4.19 g·cm−3. [5] [6] When PmCl3 is heated in the presence of H2O, the pale pink colored promethium(III) oxychloride (PmOCl) is obtained. [5] [7]
Promethium(III) chloride (with 147Pm) has been used to generate long-lasting glow in signal lights and buttons. This application relied on the unstable nature of promethium, which emitted beta radiation (electrons) with a half-life of several years. The electrons were absorbed by a phosphor, generating visible glow. [8] Unlike many other radioactive nuclides, promethium-147 does not emit alpha particles that would degrade the phosphor. [9]
Promethium is a chemical element with the symbol Pm and atomic number 61. All of its isotopes are radioactive; it is extremely rare, with only about 500–600 grams naturally occurring in Earth's crust at any given time. Promethium is one of only two radioactive elements that are followed in the periodic table by elements with stable forms, the other being technetium. Chemically, promethium is a lanthanide. Promethium shows only one stable oxidation state of +3.
Radium chloride is an inorganic compound with the chemical formula RaCl2. It is a radium salt of hydrogen chloride. It was the first radium compound isolated in a pure state. Marie Curie and André-Louis Debierne used it in their original separation of radium from barium. The first preparation of radium metal was by the electrolysis of a solution of this salt using a mercury cathode.
Iron(III) chloride describes the inorganic compounds with the formula FeCl3(H2O)x. Also called ferric chloride, these compounds are available both in anhydrous and hydrated forms which are both hygroscopic. They are common sources of iron in its +3 oxidation state. The anhydrous derivative is a Lewis acid, while the hydrate is a mild oxidizing agent. It is used as a water cleaner and as an etchant for metals.
Aluminium chloride, also known as aluminium trichloride, is an inorganic compound with the formula AlCl3. It forms a hexahydrate with the formula [Al(H2O)6]Cl3, containing six water molecules of hydration. Both the anhydrous form and the hexahydrate are colourless crystals, but samples are often contaminated with iron(III) chloride, giving them a yellow colour.
Caesium fluoride or cesium fluoride is an inorganic compound with the formula CsF and it is a hygroscopic white salt. Caesium fluoride can be used in organic synthesis as a source of the fluoride anion. Caesium also has the highest electropositivity of all known elements and fluorine has the highest electronegativity of all known elements.
Copper(I) chloride, commonly called cuprous chloride, is the lower chloride of copper, with the formula CuCl. The substance is a white solid sparingly soluble in water, but very soluble in concentrated hydrochloric acid. Impure samples appear green due to the presence of copper(II) chloride (CuCl2).
Scandium(III) nitrate, Sc(NO3)3, is an ionic compound. It is an oxidizer, as all nitrates are. The salt is applied in optical coatings, catalysts, electronic ceramics and the laser industry.
Aluminium iodide is a chemical compound containing aluminium and iodine. Invariably, the name refers to a compound of the composition AlI
3, formed by the reaction of aluminium and iodine or the action of HI on Al metal. The hexahydrate is obtained from a reaction between metallic aluminum or aluminum hydroxide with hydrogen iodide or hydroiodic acid. Like the related chloride and bromide, AlI
3 is a strong Lewis acid and will absorb water from the atmosphere. It is employed as a reagent for the scission of certain kinds of C-O and N-O bonds. It cleaves aryl ethers and deoxygenates epoxides.
Thallium(I) chloride, also known as thallous chloride, is a chemical compound with the formula TlCl. This colourless salt is an intermediate in the isolation of thallium from its ores. Typically, an acidic solution of thallium(I) sulfate is treated with hydrochloric acid to precipitate insoluble thallium(I) chloride. This solid crystallizes in the caesium chloride motif.
Protactinium(V) chloride is the chemical compound composed of protactinium and chlorine with the formula PaCl5. It forms yellow monoclinic crystals and has a unique structure composed of chains of 7 coordinate, pentagonal bipyramidal, protactinium atoms sharing edges.
Ruthenium hexafluoride, also ruthenium(VI) fluoride (RuF6), is a compound of ruthenium and fluorine and one of the seventeen known binary hexafluorides.
Uranium trifluoride is an inorganic chemical compound with the chemical formula UF3.
Calcium monosilicide (CaSi) is an inorganic compound, a silicide of calcium. It can be prepared by reacting elemental calcium and silicon at temperatures above 1000 °C. It is a Zintl phase, where silicon has oxidation state −2 and covalence 2.
Gallium(I) oxide, digallium monoxide or gallium suboxide is an inorganic compound with the formula Ga2O.
Promethium(III) fluoride or promethium trifluoride is a salt of promethium and fluorine with the formula PmF3.
Rhenium disulfide is an inorganic compound of rhenium and sulfur with the formula ReS2. It has a layered structure where atoms are strongly bonded within each layer. The layers are held together by weak Van der Waals bonds, and can be easily peeled off from the bulk material.
Praseodymium diiodide is a chemical compound with the empirical formula of PrI2, consisting of praseodymium and iodine. It is an electride, with the ionic formula of Pr3+(I−)2e−, and therefore not a true praseodymium(II) compound.
Cerium diiodide is an iodide of cerium, with the chemical formula of CeI2.
Promethium(III) iodide is an inorganic compound, with the chemical formula of PmI3. It is radioactive.
Europium(II) telluride is an inorganic compound of europium and tellurium, with the chemical formula EuTe.