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Names | |
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Other names berkelium trifluoride | |
Identifiers | |
3D model (JSmol) | |
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Properties | |
BkF3 | |
Molar mass | 304 g·mol−1 |
Appearance | yellow-green solid |
Density | 9.70 g/cm3 |
Related compounds | |
Related compounds | Berkelium tetrafluoride Einsteinium(III) fluoride |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Berkelium(III) fluoride is a binary inorganic compound of berkelium and fluorine with the chemical formula BkF
3. [1] [2] [3]
The compound can be prepared by treating Bk
2O
3 with a gaseous mixture of H
2 and HF at 600 °C. [4]
Berkelium trifluoride forms a yellow-green solid with two structures. [5] At low temperature, it is orthorhombic (YF
3 structure), with lattice parameters a = 670 pm, b = 709 pm, and c = 441 pm. At high temperature, it is trigonal (LaF
3 structure), with lattice parameters a = 697 pm and c = 714 pm. The transition temperature of BkF
3 is between 350 and 600 °C. [6] [7]
Berkelium trifluoride is reduced by lithium to obtain metallic berkelium:
Berkelium is a synthetic chemical element; it has symbol Bk and atomic number 97. It is a member of the actinide and transuranium element series. It is named after the city of Berkeley, California, the location of the Lawrence Berkeley National Laboratory where it was discovered in December 1949. Berkelium was the fifth transuranium element discovered after neptunium, plutonium, curium and americium.
Curium is a synthetic chemical element; it has symbol Cm and atomic number 96. This transuranic actinide element was named after eminent scientists Marie and Pierre Curie, both known for their research on radioactivity. Curium was first intentionally made by the team of Glenn T. Seaborg, Ralph A. James, and Albert Ghiorso in 1944, using the cyclotron at Berkeley. They bombarded the newly discovered element plutonium with alpha particles. This was then sent to the Metallurgical Laboratory at University of Chicago where a tiny sample of curium was eventually separated and identified. The discovery was kept secret until after the end of World War II. The news was released to the public in November 1947. Most curium is produced by bombarding uranium or plutonium with neutrons in nuclear reactors – one tonne of spent nuclear fuel contains ~20 grams of curium.
Few compounds of californium have been made and studied. The only californium ion that is stable in aqueous solutions is the californium(III) cation. The other two oxidation states are IV (strong oxidizing agents) and II (strong reducing agents). The element forms a water-soluble chloride, nitrate, perchlorate, and sulfate and is precipitated as a fluoride, oxalate or hydroxide. If problems of availability of the element could be overcome, then CfBr2 and CfI2 would likely be stable.
Berkelium forms a number of chemical compounds, where it normally exists in an oxidation state of +3 or +4, and behaves similarly to its lanthanide analogue, terbium. Like all actinides, berkelium easily dissolves in various aqueous inorganic acids, liberating gaseous hydrogen and converting into the trivalent oxidation state. This trivalent state is the most stable, especially in aqueous solutions, but tetravalent berkelium compounds are also known. The existence of divalent berkelium salts is uncertain and has only been reported in mixed lanthanum chloride-strontium chloride melts. Aqueous solutions of Bk3+ ions are green in most acids. The color of the Bk4+ ions is yellow in hydrochloric acid and orange-yellow in sulfuric acid. Berkelium does not react rapidly with oxygen at room temperature, possibly due to the formation of a protective oxide surface layer; however, it reacts with molten metals, hydrogen, halogens, chalcogens and pnictogens to form various binary compounds. Berkelium can also form several organometallic compounds.
Californium(III) bromide is an inorganic compound, a salt with a chemical formula CfBr3. Like in californium oxide (Cf2O3) and other californium halides, including californium(III) fluoride (CfF3), californium(III) chloride, and californium(III) iodide (CfI3), the californium atom has an oxidation state of +3.
Berkelium(IV) oxide, also known as berkelium dioxide, is a chemical compound with the formula BkO2. This compound slowly decays to californium(IV) oxide. It can be converted to berkelium(III) oxide by hydrogen reduction at 600 °C.
Curium compounds are compounds containing the element curium (Cm). Curium usually forms compounds in the +3 oxidation state, although compounds with curium in the +4, +5 and +6 oxidation states are also known.
Curium(III) bromide is the bromide salt of curium. It has an orthorhombic crystal structure.
Einsteinium compounds are compounds that contain the element einsteinium (Es). These compounds largely have einsteinium in the +3 oxidation state, or in some cases in the +2 and +4 oxidation states. Although einsteinium is relatively stable, with half-lives ranging from 20 days upwards, these compounds have not been studied in great detail.
Berkelium(III) chloride also known as berkelium trichloride, is a chemical compound with the formula BkCl3. It is a water-soluble green salt with a melting point of 603 °C. This compound forms the hexahydrate, BkCl3·6H2O.
Americium compounds are compounds containing the element americium (Am). These compounds can form in the +2, +3, and +4, although the +3 oxidation state is the most common. The +5, +6 and +7 oxidation states have also been reported.
Berkelium tetrafluoride is a binary inorganic compound of berkelium and fluorine with the chemical formula BkF4.
Californium(III) fluoride is a binary inorganic compound of californium and fluorine with the formula CfF
3
Californium(III) oxide is a binary inorganic compound of californium and oxygen with the formula Cf
2O
3. It is one of the first obtained solid compounds of californium, synthesized in 1958.
Californium(II) iodide is a binary inorganic compound of californium and iodine with the formula CfI
2.
Berkelium(III) oxide is a binary inorganic compound of berkelium and oxygen with the chemical formula Bk
2O
3.
Berkelium bromide is a bromide of berkelium, with the chemical formula BkBr3.
Curium(IV) fluoride is an inorganic chemical compound, a salt of curium and fluorine with the chemical formula CmF4.
Einsteinium fluoride is a binary inorganic chemical compound of einsteinium and fluorine with the chemical formula EsF3.
Berkelium(III) phosphide is a binary inorganic compound of berkelium and phosphorus with the chemical formula BkP.