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Rhenium Trioxide Fluoride
Rhenium trioxide fluoride is an inorganic compound with the formula . It is a white, sublimable, diamagnetic solid, although impure samples appear colored. It one of the few oxyfluorides of rhenium, the other major one being rhenium dioxide trifluoride . The material has no applications, but it is of some academic interest as a rare example of a trioxide fluoride. Synthesis and reactions Rhenium trioxide fluoride can be prepared by fluorination of rhenium trioxide: : With Lewis bases (L) the compound forms adducts with the formula , e.g., L = diethyl ether and acetonitrile. Structure and related compounds According to X-ray crystallography, the compound adopts a helical chain structure featuring octahedral Re centers linked by two fluoride and two oxide bridging ligands. In contrast with , and crystallize with simpler structures. The Mn compound crystallizes as a tetrahedral monomer. The technetium compound crystallizes as dimers with fluoride bridges. Also contrasting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inorganic Compound
An inorganic compound is typically a chemical compound that lacks carbon–hydrogen bondsthat is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as ''inorganic chemistry''. Inorganic compounds comprise most of the Earth's crust, although the compositions of the deep Mantle (geology), mantle remain active areas of investigation. All allotropes (structurally different pure forms of an element) and some simple carbon compounds are often considered inorganic. Examples include the allotropes of carbon (graphite, diamond, buckminsterfullerene, graphene, etc.), carbon monoxide , carbon dioxide , carbides, and salt (chemistry), salts of inorganic anions such as carbonates, cyanides, cyanates, thiocyanates, isothiocyanates, etc. Many of these are normal parts of mostly organic systems, including organisms; describing a chemical as inorganic does not necessarily mean that it cannot occur within life, living things. History ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhenium Dioxide Trifluoride
Rhenium dioxide trfluoride is an inorganic compound with the formula . A white diamagnetic solid, it one of the few oxyfluorides of rhenium, another being rhenium trioxide fluoride, . The material is of some academic interest as a rare example of an dioxide trifluoride. It can be prepared by the reaction of xenon difluoride and rhenium trioxide chloride: : According to X-ray crystallography, the compound can exist in four polymorphs. Two polymorphs adopt chain-like structures featuring octahedral Re centers linked by ridging bridging fluorides. Two other polymorphs adopt cyclic structures and , again featuring octahedral Re centers and bridging fluorides. Like related oxyfluorides, these coordination oligomers break up in the presence of Lewis bases. Adducts of the formula where L = acetonitrile Acetonitrile, often abbreviated MeCN (methyl cyanide), is the chemical compound with the formula and structure . This colourless liquid is the simplest organic nitrile (hydrog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluorination
In chemistry, halogenation is a chemical reaction which introduces one or more halogens into a chemical compound. Halide-containing compounds are pervasive, making this type of transformation important, e.g. in the production of polymers, drugs. This kind of conversion is in fact so common that a comprehensive overview is challenging. This article mainly deals with halogenation using elemental halogens (). Halides are also commonly introduced using salts of the halides and halogen acids. Many specialized reagents exist for introducing halogens into diverse substrates, e.g. thionyl chloride. Organic chemistry Several pathways exist for the halogenation of organic compounds, including free radical halogenation, ketone halogenation, electrophilic halogenation, and halogen addition reaction. The nature of the substrate determines the pathway. The facility of halogenation is influenced by the halogen. Fluorine and chlorine are more electrophilic and are more aggressive halogenati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhenium Trioxide
Rhenium trioxide or rhenium(VI) oxide is an inorganic compound with the formula ReO3. It is a red solid with a metallic lustre that resembles copper in appearance. It is the only stable trioxide of the Group 7 elements ( Mn, Tc, Re). Preparation and structure Rhenium trioxide can be formed by reducing rhenium(VII) oxide with carbon monoxide at 200 °C or elemental rhenium at 400 °C. :Re2O7 + CO → 2 ReO3 + CO2 :3 Re2O7 + Re → 7 ReO3 Re2O7 can also be reduced with dioxane. Rhenium trioxide crystallizes with a primitive cubic unit cell, with a lattice parameter of 3.742 Å (374.2 pm). The structure of ReO3 is similar to that of perovskite (ABO3), without the large A cation at the centre of the unit cell. Each rhenium center is surrounded by an octahedron defined by six oxygen centers. These octahedra share corners to form the 3-dimensional structure. The coordination number of O is 2, because each oxygen atom has 2 neighbouring Re atoms., p. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lewis Base
A Lewis acid (named for the American physical chemist Gilbert N. Lewis) is a chemical species that contains an empty orbital which is capable of accepting an electron pair from a Lewis base to form a Lewis adduct. A Lewis base, then, is any species that has a filled orbital containing an electron pair which is not involved in bonding but may form a dative bond with a Lewis acid to form a Lewis adduct. For example, NH3 is a Lewis base, because it can donate its lone pair of electrons. Trimethylborane CH3)3Bis a Lewis acid as it is capable of accepting a lone pair. In a Lewis adduct, the Lewis acid and base share an electron pair furnished by the Lewis base, forming a dative bond. In the context of a specific chemical reaction between NH3 and Me3B, a lone pair from NH3 will form a dative bond with the empty orbital of Me3B to form an adduct NH3•BMe3. The terminology refers to the contributions of Gilbert N. Lewis. From p. 142: "We are inclined to think of substances as pos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diethyl Ether
Diethyl ether, or simply ether, is an organic compound with the chemical formula , sometimes abbreviated as . It is a colourless, highly Volatility (chemistry), volatile, sweet-smelling ("ethereal odour"), extremely flammable liquid. It belongs to the ether class of organic compounds. It is a common solvent and was formerly used as a general anesthetic. Production Most diethyl ether is produced as a byproduct of the vapor-phase Hydration reaction, hydration of ethylene to make ethanol. This process uses solid-supported phosphoric acid Catalysis, catalysts and can be adjusted to make more ether if the need arises: Vapor-phase Dehydration reaction, dehydration of ethanol over some Aluminium oxide, alumina catalysts can give diethyl ether yields of up to 95%. : Diethyl ether can be prepared both in laboratories and on an industrial scale by the acid ether synthesis. Uses The dominant use of diethyl ether is as a solvent. One particular application is in the production of cell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetonitrile
Acetonitrile, often abbreviated MeCN (methyl cyanide), is the chemical compound with the formula and structure . This colourless liquid is the simplest organic nitrile (hydrogen cyanide is a simpler nitrile, but the cyanide anion is not classed as organic). It is produced mainly as a byproduct of acrylonitrile manufacture. It is used as a polar aprotic solvent in organic synthesis and in the purification of butadiene. The skeleton is linear with a short distance of 1.16 Å. Acetonitrile was first prepared in 1847 by the French chemist Jean-Baptiste Dumas. Applications Acetonitrile is used mainly as a solvent in the purification of butadiene in refineries. Specifically, acetonitrile is fed into the top of a distillation column filled with hydrocarbons including butadiene, and as the acetonitrile falls down through the column, it absorbs the butadiene which is then sent from the bottom of the tower to a second separating tower. Heat is then employed in the separa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-ray Crystallography
X-ray crystallography is the experimental science of determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to Diffraction, diffract in specific directions. By measuring the angles and intensities of the X-ray diffraction, a crystallography, crystallographer can produce a three-dimensional picture of the density of electrons within the crystal and the positions of the atoms, as well as their chemical bonds, crystallographic disorder, and other information. X-ray crystallography has been fundamental in the development of many scientific fields. In its first decades of use, this method determined the size of atoms, the lengths and types of chemical bonds, and the atomic-scale differences between various materials, especially minerals and alloys. The method has also revealed the structure and function of many biological molecules, including vitamins, drugs, proteins and nucleic acids such as DNA. X-ray crystall ... [...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] |
Bridging Ligand
In coordination chemistry, a bridging ligand is a ligand that connects two or more atoms, usually metal ions. The ligand may be atomic or polyatomic. Virtually all complex organic compounds can serve as bridging ligands, so the term is usually restricted to small ligands such as pseudohalides or to ligands that are specifically designed to link two metals. In naming a complex wherein a single atom bridges two metals, the bridging ligand is preceded by the Greek letter mu, μ, with a subscript number denoting the number of metals bound to the bridging ligand. μ2 is often denoted simply as μ. When describing coordination complexes care should be taken not to confuse μ with η ('eta'), which relates to hapticity. Ligands that are not bridging are called terminal ligands. List of bridging ligands Virtually all ligands are known to bridge, with the exception of amines and ammonia. Common bridging ligands include most of the common anions. Many simple organic ligands form s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manganese Trioxide Fluoride
Manganese trioxide fluoride is an inorganic compound with the formula . A green diamagnetic liquid, the compound has no applications, but it is of some academic interest as a rare example of a metal trioxide fluoride. The compound was detected in the 1880s but was only purified and crystallized much more recently. It can be prepared by fluorosulfuric acid and potassium permanganate: : crystallizes as a monomer, as confirmed by X-ray crystallography. The molecules are tetrahedral with Mn-O and Mn-F distances of 1.59 and 1.72 Å, respectively. In contrast with , and have more complex structures as solids. The Re compound crystallizes as chains or rings consisting of fluoride-bridge octahedra. crystallizes as dimers with fluoride bridges. The rhenium compound also forms stable adducts with Lewis base A Lewis acid (named for the American physical chemist Gilbert N. Lewis) is a chemical species that contains an empty orbital which is capable of accepting an electron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhenium Trioxide Chloride
Rhenium trioxide chloride is an inorganic compound with the formula . It is a colorless, distillable, diamagnetic liquid. It is a rhenium oxychloride. The material is used as a reagent in the preparation of rhenium compounds. Synthesis and reactions Rhenium trioxide chloride can be prepared by chlorination of rhenium trioxide: : With Lewis base A Lewis acid (named for the American physical chemist Gilbert N. Lewis) is a chemical species that contains an empty orbital which is capable of accepting an electron pair from a Lewis base to form a Lewis adduct. A Lewis base, then, is any sp ...s (L), rhenium trioxide chloride reacts to form adducts with the formula . The compound hydrolyzes readily to give perrhenic acid. Structure The compound adopts a tetrahedral structure with Re-O and Re-Cl bond distances of 1.71 and 2.22 Å. In contrast rhenium trioxide fluoride () is polymeric with octahedral Re centers. References {{Reflist Rhenium compounds Chlorides Transition ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
