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Chromium Oxytetrafluoride
Chromium oxytetrafluoride is the inorganic compound with the formula . It is a purple, volatile, diamagnetic solid. The compound is classified as an oxyfluoride. Synthesis It can be prepared by fluorination of chromyl fluoride with krypton difluoride: : The compound serves as a weak 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 ... with noble gas difluorides. It also binds fluoride to give the pentafluoride. References {{fluorine compounds Chromium(VI) compounds Chromium–halogen compounds Oxyfluorides Chromium–oxygen compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molybdenum Oxytetrafluoride
Molybdenum is a chemical element; it has symbol Mo (from Neo-Latin ''molybdaenum'') and atomic number 42. The name derived from Ancient Greek ', meaning lead, since its ores were confused with lead ores. Molybdenum minerals have been known throughout history, but the element was discovered (in the sense of differentiating it as a new entity from the mineral salts of other metals) in 1778 by Carl Wilhelm Scheele. The metal was first isolated in 1781 by Peter Jacob Hjelm. Molybdenum does not occur naturally as a free metal on Earth; in its minerals, it is found only in oxidized states. The free element, a silvery metal with a grey cast, has the sixth-highest melting point of any element. It readily forms hard, stable carbides in alloys, and for this reason most of the world production of the element (about 80%) is used in steel alloys, including high-strength alloys and superalloys. Most molybdenum compounds have low solubility in water. Heating molybdenum-bearing minerals under ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tungsten Oxytetrafluoride
Tungsten oxytetrafluoride is an inorganic compound with the formula . It is a colorless diamagnetic solid. The compound is one of many oxides of tungsten. It is usually encountered as product of the partial hydrolysis of tungsten hexafluoride. Structure As confirmed by X-ray crystallography, crystallizes as a tetramer. The oxides are terminal, and four of the fluorides are bridging ligand, bridging. Its structure is similar to those for niobium pentafluoride and tantalum pentafluoride. In contrast, molybdenum oxytetrafluoride adopts a polymeric structure, although again the fluorides bridge and the oxides are terminal. In the gas state, this molecule is a monomer. It can form complexes with acetonitrile and other compounds. Preparation Tungsten(VI) oxytetrafluoride can be synthesized by the reaction of fluorine and tungsten trioxide. It can also be obtained by treating tungsten with a mixture of oxygen and fluorine at high temperatures. Partial hydrolysis of tungsten hexaflu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromyl Fluoride
Chromyl fluoride is an inorganic compound with the formula . It is a violet-red colored crystalline solid that melts to an orange-red liquid.Gard, G. L. (1986) "Chromium Difluoride Dioxide (Chromyl Fluoride)," '' Inorg. Synth.'', 24, 67-69, . Structure The liquid and gaseous have a tetrahedral geometry with C2v symmetry, much like chromyl chloride. Chromyl fluoride dimerizes via fluoride bridges (as ) in the solid state, crystallizing in the P21/c space group with Z = 4. The Cr=O bond lengths are about 157 pm, and the Cr–F bond lengths are 181.7, 186.7, and 209.4 pm. Chromium resides in a distorted octahedral position with a coordination number of 6. History and preparation Pure chromyl fluoride was first isolated in 1952 as reported by Alfred Engelbrecht and Aristid von Grosse.Engelbrecht, A.; von Grosse, A. (1952) "Pure Chromyl Fluoride," '' J. Am. Chem. Soc.'' 74(''21''), 5262–5264, . It was first observed as red vapor in the early 19th century upon heatin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thionyl Tetrafluoride
Thionyl tetrafluoride, also known as sulfur tetrafluoride oxide, is an inorganic compound with the formula . It is a colorless gas. The shape of the molecule is a distorted trigonal bipyramid, with the oxygen found on the equator. The atoms on the equator have shorter bond lengths than the fluorine atoms on the axis. In the gas-phase, the sulfur-oxygen bond is 1.409 Å. The S−F bond on the axis has length 1.596 Å and the S−F bond on the equator has length 1.539 Å. The angle between the equatorial fluorine atoms is 112.8°. The angle between axial fluorine and oxygen is 97.7°. The angle between oxygen and equatorial fluorine is 123.6° and between axial and equatorial fluorine is 85.7°. Slight variations of bonds lengths and angles has been observed in solid-state by X-ray analysis. The fluorine atoms only produce one NMR line, probably because they exchange positions. It is isoelectronic with phosphorus pentafluoride. Formation Thionyl fluoride reacting with fluorine gas ... [...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] |
Diamagnetic
Diamagnetism is the property of materials that are repelled by a magnetic field; an applied magnetic field creates an induced magnetic field in them in the opposite direction, causing a repulsive force. In contrast, paramagnetic and ferromagnetic materials are attracted by a magnetic field. Diamagnetism is a quantum mechanical effect that occurs in all materials; when it is the only contribution to the magnetism, the material is called diamagnetic. In paramagnetic and ferromagnetic substances, the weak diamagnetic force is overcome by the attractive force of magnetic dipoles in the material. The magnetic permeability of diamagnetic materials is less than the permeability of vacuum, ''μ''0. In most materials, diamagnetism is a weak effect which can be detected only by sensitive laboratory instruments, but a superconductor acts as a strong diamagnet because it entirely expels any magnetic field from its interior (the Meissner effect). Diamagnetism was first discovered whe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxyfluoride
In chemistry, oxohalides or oxyhalides are a group of chemical compounds with the chemical formula , where X is a halogen, and A is an element different than O and X. Known oxohalides have fluorine (F), chlorine (Cl), bromine (Br), and/or iodine (I). The element A may be a main group element, a transition element, a rare earth element or an actinide. Molecular oxohalides are a group of chemical compounds in which both oxygen and halogen atoms are attached to another chemical element A in a single molecule. The term ''oxohalide'', or ''oxyhalide'', also refers to ionic oxohalides with the same overall chemical formula, but having an ionic structure. There are minerals that are ionic oxohalides. Synthesis Oxohalides can be seen as compounds intermediate between oxides and halides. There are three general methods of synthesis: *Partial oxidation of a halide: *: **In this example, the oxidation state increases by two and the electrical charge is unchanged. *Partial halogenation of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of The Chemical Society, Dalton Transactions
''Dalton Transactions'' is a weekly peer-reviewed scientific journal covering original (primary) research and review articles on all aspects of the chemistry of inorganic, bioinorganic, and organometallic compounds. It is published by the Royal Society of Chemistry and the editor-in-chief is Russell Morris (University of St Andrews). The journal was named after the English chemist, John Dalton, best known for his work on modern atomic theory. The journal was named a "rising star" in 2006. Publication history The journal was established as the ''Journal of the Chemical Society A: Inorganic, Physical, Theoretical'' in 1966. In 1972, the journal was divided into three separate journals: ''Journal of the Chemical Society, Dalton Transactions'' (covering inorganic and organometallic chemistry), '' Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases'', and '' Journal of the Chemical Society, Faraday Transactions 2: Molecular and Chemical Phy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromyl Fluoride
Chromyl fluoride is an inorganic compound with the formula . It is a violet-red colored crystalline solid that melts to an orange-red liquid.Gard, G. L. (1986) "Chromium Difluoride Dioxide (Chromyl Fluoride)," '' Inorg. Synth.'', 24, 67-69, . Structure The liquid and gaseous have a tetrahedral geometry with C2v symmetry, much like chromyl chloride. Chromyl fluoride dimerizes via fluoride bridges (as ) in the solid state, crystallizing in the P21/c space group with Z = 4. The Cr=O bond lengths are about 157 pm, and the Cr–F bond lengths are 181.7, 186.7, and 209.4 pm. Chromium resides in a distorted octahedral position with a coordination number of 6. History and preparation Pure chromyl fluoride was first isolated in 1952 as reported by Alfred Engelbrecht and Aristid von Grosse.Engelbrecht, A.; von Grosse, A. (1952) "Pure Chromyl Fluoride," '' J. Am. Chem. Soc.'' 74(''21''), 5262–5264, . It was first observed as red vapor in the early 19th century upon heatin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Krypton Difluoride
Krypton difluoride, KrF2 is a chemical compound of krypton and fluorine. It was the first compound of krypton discovered. It is a volatile, colourless solid at room temperature. The structure of the KrF2 molecule is linear, with Kr−F distances of 188.9 pm. It reacts with strong Lewis acids to form salts of the KrF+ and Kr cations. The atomization energy of KrF2 (KrF2(g) → Kr(g) + 2 F(g)) is 21.9 kcal/mol, giving an average Kr–F bond energy of only 11 kcal/mol, the weakest of any isolable fluoride. In comparison, the dissociation of difluorine to atomic fluorine requires cleaving a F–F bond with a bond dissociation energy of 36 kcal/mol. Consequently, KrF2 is a good source of the extremely reactive and oxidizing atomic fluorine. It is thermally unstable, with a decomposition rate of 10% per hour at room temperature. The formation of krypton difluoride is endothermic, with a heat of formation (gas) of 14.4 ± 0.8 kcal/mol measured at 93 °C. Synthesis Krypton difluor ... [...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] |
Chromium(VI) Compounds
Chromium is a chemical element; it has symbol Cr and atomic number 24. It is the first element in group 6. It is a steely-grey, lustrous, hard, and brittle transition metal. Chromium is valued for its high corrosion resistance and hardness. A major development in steel production was the discovery that steel could be made highly resistant to corrosion and discoloration by adding metallic chromium to form stainless steel. Stainless steel and chrome plating (electroplating with chromium) together comprise 85% of the commercial use. Chromium is also greatly valued as a metal that is able to be highly polished while resisting tarnishing. Polished chromium reflects almost 70% of the visible spectrum, and almost 90% of infrared light. The name of the element is derived from the Greek word χρῶμα, ''chrōma'', meaning color, because many chromium compounds are intensely colored. Industrial production of chromium proceeds from chromite ore (mostly FeCr2O4) to produce ferrochrom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
