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Oxybismuthide
Oxybismuthides or bismuthide oxides are chemical compounds formally containing the group BiO, with one bismuth and one oxygen atom. The bismuth and oxygen are not bound together as in bismuthates, instead they make a separate presence bound to the cations (metals), and could be considered as a mixed bismuthide-oxide compound. So a compound with OmBin requires cations to balance a negative charge of 2m+3n. The cations will have charges of +2 or +3. The trications are often rare earth elements or actinides. They are in the category of oxypnictide In chemistry, oxypnictides are a class of materials composed of oxygen, a pnictogen (group-V, especially phosphorus and arsenic) and one or more other elements. Although this group of compounds has been recognized since 1995, interest in these com ... compounds. Many of the bismuthide oxides have bismuth in an unusual −2 oxidation state. The ones with Ln2BiO2 have the anti-ThCr2Si2 structure. They include alternating layers of LnO ( anti- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxypnictide
In chemistry, oxypnictides are a class of materials composed of oxygen, a pnictogen (group-V, especially phosphorus and arsenic) and one or more other elements. Although this group of compounds has been recognized since 1995, interest in these compounds increased dramatically after the publication of the superconducting properties of LaOFeP and LaOFeAs which were discovered in 2006 and 2008. In these experiments the oxide was partly replaced by fluoride. These and related compounds (e.g. the 122 iron arsenides) form a new group of iron-based superconductors known as iron pnictides or ferropnictides since the oxygen is not essential but the iron seems to be. Oxypnictides have been patented as magnetic semiconductors in early 2006. The different subclasses of oxypnictides are oxynitrides, oxyphosphides, oxyarsenides, oxyantimonides, and oxybismuthides. Structure Many of the oxypnictides show a layered structure. For example, LaFePO with layers of La3+O2− and Fe2+P3−. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bismuth
Bismuth is a chemical element; it has symbol Bi and atomic number 83. It is a post-transition metal and one of the pnictogens, with chemical properties resembling its lighter group 15 siblings arsenic and antimony. Elemental bismuth occurs naturally, and its sulfide and oxide forms are important commercial ores. The free element is 86% as dense as lead. It is a brittle metal with a silvery-white color when freshly produced. Surface oxidation generally gives samples of the metal a somewhat rosy cast. Further oxidation under heat can give bismuth a vividly iridescent appearance due to thin-film interference. Bismuth is both the most diamagnetic element and one of the least thermally conductive metals known. Bismuth was formerly understood to be the element with the highest atomic mass whose nuclei do not spontaneously decay. However, in 2003 it was found to be very slightly radioactive. The metal's only primordial isotope, bismuth-209, undergoes alpha decay with a half-l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen
Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), nonmetal, and a potent oxidizing agent that readily forms oxides with most elements as well as with other chemical compound, compounds. Oxygen is abundance of elements in Earth's crust, the most abundant element in Earth's crust, making up almost half of the Earth's crust in the form of various oxides such as water, carbon dioxide, iron oxides and silicates.Atkins, P.; Jones, L.; Laverman, L. (2016).''Chemical Principles'', 7th edition. Freeman. It is abundance of chemical elements, the third-most abundant element in the universe after hydrogen and helium. At standard temperature and pressure, two oxygen atoms will chemical bond, bind covalent bond, covalently to form dioxygen, a colorless and odorless diatomic gas with the chemical formula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bismuthate
Bismuthate is an ion. Its chemical formula is . It has bismuth in its +5 oxidation state. It is a very strong oxidizing agent. It reacts with hot water to make bismuth(III) oxide and oxygen. It also reacts with acids. Sodium bismuthate is the most common bismuthate. It is one of the few sodium compounds Sodium atoms have 11 electrons, one more than the stable configuration of the noble gas neon. As a result, sodium usually forms ionic compounds involving the Na+ cation. Sodium is a reactive alkali metal and is much more stable in ionic compounds ... that does not dissolve in water. Related pages * Bismuth(III) chloride * Bismuth(V) fluoride, the other bismuth compound in its +5 oxidation state * Sodium bismuthate * Sodium bismuth titanate References Bismuth compounds Oxometallates {{chem-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bismuthide
The bismuthide ion is but the term is often used to describe less reduced forms of bismuth. Bismuthides are compounds of bismuth with more electropositive elements. A wide variety are known. The stoichiometry of bismuthides ranges from lithium bismuthide (Li3Bi), which can be viewed as the Li+ salt of Bi3-. The corresponding sodium and potassium derivatives are also known. They all prepared by heating the elements. In terms of Bi-rich phases, examples are LiBi, KBi2, CaBi3, which exhibit strong Bi-Bi bonding. Some are intermetallic compounds, containing partially metallic and partially ionic bonds. The majority of bismuthides adopt efficient packing arrangements and become densely packed structures, which is a characteristic of intermetallic compounds. See also * Bismanol Bismanol is a magnetic alloy of bismuth and manganese (manganese bismuthide) developed by the US Naval Ordnance Laboratory. History Bismanol, a permanent magnet made from powder metallurgy of man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxide
An oxide () is a chemical compound containing at least one oxygen atom and one other element in its chemical formula. "Oxide" itself is the dianion (anion bearing a net charge of −2) of oxygen, an O2− ion with oxygen in the oxidation state of −2. Most of the Earth's crust consists of oxides. Even materials considered pure elements often develop an oxide coating. For example, aluminium foil develops a thin skin of (called a passivation layer) that protects the foil from further oxidation.Greenwood, N. N.; & Earnshaw, A. (1997). Chemistry of the Elements (2nd Edn.), Oxford:Butterworth-Heinemann. . Stoichiometry Oxides are extraordinarily diverse in terms of stoichiometries (the measurable relationship between reactants and chemical equations of an equation or reaction) and in terms of the structures of each stoichiometry. Most elements form oxides of more than one stoichiometry. A well known example is carbon monoxide and carbon dioxide.Greenwood, N. N.; & Earnsh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cation
An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by convention. The net charge of an ion is not zero because its total number of electrons is unequal to its total number of protons. A cation is a positively charged ion with fewer electrons than protons (e.g. K+ ( potassium ion)) while an anion is a negatively charged ion with more electrons than protons (e.g. Cl− ( chloride ion) and OH− ( hydroxide ion)). Opposite electric charges are pulled towards one another by electrostatic force, so cations and anions attract each other and readily form ionic compounds. Ions consisting of only a single atom are termed ''monatomic ions'', ''atomic ions'' or ''simple ions'', while ions consisting of two or more atoms are termed polyatomic ions or ''molecular ions''. If only a + or − is present, it indic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rare Earth Element
The rare-earth elements (REE), also called the rare-earth metals or rare earths, and sometimes the lanthanides or lanthanoids (although scandium and yttrium, which do not belong to this series, are usually included as rare earths), are a set of 17 nearly indistinguishable lustrous silvery-white soft heavy metals. Compounds containing rare earths have diverse applications in electrical and electronic components, lasers, glass, magnetic materials, and industrial processes. The term "rare-earth" is a misnomer because they are not actually scarce, but historically it took a long time to isolate these elements. They are relatively plentiful in the entire Earth's crust ( cerium being the 25th-most-abundant element at 68 parts per million, more abundant than copper), but in practice they are spread thinly as trace impurities, so to obtain rare earths at usable purity requires processing enormous amounts of raw ore at great expense; thus the name "rare" earths. Scandium and yttrium a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Actinide
The actinide () or actinoid () series encompasses at least the 14 metallic chemical elements in the 5f series, with atomic numbers from 89 to 102, actinium through nobelium. Number 103, lawrencium, is also generally included despite being part of the 6d transition series. The actinide series derives its name from the first element in the series, actinium. The informal chemical symbol An is used in general discussions of actinide chemistry to refer to any actinide. The 1985 IUPAC nomenclature of inorganic chemistry, IUPAC ''Red Book'' recommends that ''actinoid'' be used rather than ''actinide'', since the suffix ''-ide'' normally indicates a negative ion. However, owing to widespread current use, ''actinide'' is still allowed. Actinium through nobelium are f-block elements, while lawrencium is a d-block element and a transition metal. The series mostly corresponds to the filling of the 5f electron shell, although as isolated atoms in the ground state many have anomalous configu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anti-fluorite Structure
The fluorite structure refers to a common motif for compounds with the formula MX2. The X ions occupy the eight tetrahedral interstitial sites whereas M ions occupy the regular sites of a face-centered cubic (FCC) structure. Many compounds, notably the common mineral fluorite (CaF2), adopt this structure. Many compounds with formula M2X have an antifluorite structure. In these the locations of the anions and cations are reversed relative to fluorite (an anti-structure); the anions occupy the FCC regular sites whereas the cations occupy the tetrahedral interstitial sites. For example, magnesium silicide, Mg2Si, has a lattice parameter of 6.338 Å with magnesium cations occupying the tetrahedral interstitial sites, in which each silicide anion is surrounded by eight magnesium cations and each magnesium cation is surrounded by four silicide anions in a tetrahedral fashion. File:Fluorite Structure.jpg, The fluorite structure of calcium fluoride CaF2. File:Antifluorite Structure.jpg, T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bismuth Compounds
Bismuth forms mainly trivalent and a few pentavalent compounds. Many of its chemical properties are similar to those of arsenic and antimony, although much less toxic. Oxides and sulfides At elevated temperatures, vaporized bismuth metal and oxygen combine into the yellow trioxide, . Wiberg, p. 768. Greenwood, p. 553. At temperatures above 710 °C, this (molten) oxide corrodes all known oxides and even platinum. Krüger, p. 185 It forms two series of oxyanions in basic conditions: linear, chain-polymeric ; and cubic . In , the anion forms the octamer ; in , the tetramer. The dark red bismuth(V) oxide, , is unstable, liberating gas upon heating. The compound NaBiO3 is a strong oxidant. Greenwood, p. 578. Bismuth sulfide, , occurs naturally in bismuth ores, but can be synthesized from molten bismuth and sulfur. Greenwood, pp. 559–561. Halides In oxidation state +3, bismuth forms salts with all the halogens: , , , and . All hydrolyze in water except . Bismuth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
