Names | |
---|---|
Other names berkelium(IV) fluoride | |
Identifiers | |
3D model (JSmol) | |
| |
| |
Properties | |
BkF4 | |
Molar mass | 323 g·mol−1 |
Appearance | yellow-green solid |
practically insoluble | |
Structure | |
monoclinic | |
Related compounds | |
Related compounds | Curium(III) fluoride, berkelium trifluoride |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Berkelium tetrafluoride is a binary inorganic compound of berkelium and fluorine with the chemical formula BkF4. [1]
Berkelium tetrafluoride may be formed by the fluorination of berkelium trioxide, dioxide, or trifluoride with elemental fluorine at elevated temperatures:
Berkelium(IV) fluoride forms light brown crystals of monoclinic crystal structure of uranium tetrafluoride type. Cell parameters: a = 1.2396 nm, b = 1.0466 nm, c = 0.8118 nm, angle β = 126.33°. [2] [3]
Berkelium tetrafluoride is reduced by lithium at elevated temperatures to metallic berkelium: [4]
Americium is a synthetic chemical element; it has symbol Am and atomic number 95. It is radioactive and a transuranic member of the actinide series in the periodic table, located under the lanthanide element europium and was thus named after the Americas by analogy.
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.
Plutonium hexafluoride is the highest fluoride of plutonium, and is of interest for laser enrichment of plutonium, in particular for the production of pure plutonium-239 from irradiated uranium. This isotope of plutonium is needed to avoid premature ignition of low-mass nuclear weapon designs by neutrons produced by spontaneous fission of plutonium-240.
Iridium(IV) fluoride is a chemical compound of iridium and fluorine, with the chemical formula IrF4 and is a dark brown solid. Early reports of IrF4 prior to 1965 are questionable and appear to describe the compound IrF5. The solid can be prepared by reduction of IrF5 with iridium black or reduction with H2 in aqueous HF. The crystal structure of the solid is notable as it was the first example of a three-dimensional lattice structure found for a metal tetrafluoride and subsequently RhF4, PdF4 and PtF4 have been found to have the same structure. The structure has 6 coordinate, octahedral, iridium where two edges of the octahedra are shared and the two unshared fluorine atoms are cis to one another.
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.
Americium(III) iodide or americium triiodide is the chemical compound, a salt composed of americium and iodine with the formula AmI3.
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.
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.
Berkelium(III) fluoride is a binary inorganic compound of berkelium and fluorine with the chemical formula BkF
3.
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 of curium and fluorine with the chemical formula CmF4.
Curium(IV) oxide is an inorganic chemical compound of curium and oxygen with the chemical formula CmO2. Since all isotopes of curium are man-made, the compound does not occur in nature.
Curium(III) iodide is the chemical compound with the formula CmI3. Since all isotopes of curium are only artificially produced, the compound has no natural occurrence.