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Vanadyl
The vanadyl or oxovanadium(IV) cation, VO2+, is a functional group that is common in the coordination chemistry of vanadium. Complexes containing this functional group are characteristically blue and paramagnetic. A triple bond is proposed to exist between the V4+ and O2− centers. The description of the bonding in the vanadyl ion was central to the development of modern ligand-field theory. Natural occurrence Minerals Cavansite and pentagonite are vanadyl-containing minerals. Water VO2+, often in an ionic pairing with sodium (NaH2VO4), is the second most abundant transition metal in seawater, with its concentration only being exceeded by molybdenum. In the ocean the average concentration is 30 nM. Some mineral water springs also contain the ion in high concentrations. For example, springs near Mount Fuji often contain as much as 54 μg per liter. Vanadyl containing compounds Oxovanadium(IV) * vanadyl acetylacetonate, VO(acac)2 * vanadyl sulfate, VOSO4 * van ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vanadyl Sulfate
Vanadyl(IV) sulfate describes a collection of inorganic compounds of vanadium with the formula, VOSO4(H2O)x where 0 ≤ x ≤ 6. The pentahydrate is common. This hygroscopic blue solid is one of the most common sources of vanadium in the laboratory, reflecting its high stability. It features the vanadyl ion, VO2+, which has been called ''the'' "most stable diatomic ion". Vanadyl sulfate is an intermediate in the extraction of vanadium from petroleum residues, one commercial source of vanadium. Synthesis, structure, and reactions Vanadyl sulfate is most commonly obtained by reduction of vanadium pentoxide with sulfur dioxide: : From aqueous solution, the salt crystallizes as the pentahydrate, the fifth water is not bound to the metal in the solid. Viewed as a coordination complex, the ion is octahedral, with oxo, four equatorial water ligands, and a monodentate sulfate. The trihydrate has also been examined by crystallography. A hexahydrate exists below . Two polymorphs of anhy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vanadyl Nitrate
Vanadyl nitrate, also called vanadium oxytrinitrate or vanadium oxynitrate is an inorganic compound of vanadium in the +5 oxidation state with nitrate ligands and oxygen. The formula is VO(NO3)3. It is a pale yellow viscous liquid. Production It is made by soaking vanadium pentoxide in liquid dinitrogen pentoxide for durations around two days at room temperature. The yield for this method is about 85%. :V2O5 + 3 N2O5 → 2 VO(NO3)3. Purification can be achieved by vacuum distillation. Mononitratodioxovanadium (VO2NO3) is an intermediate in this synthesis. It is a brick red solid. Vanadyl nitrate can also be made from vanadyl trichloride VOCl3 and dinitrogen pentoxide. Structure VO(NO3)3 has a distorted pentagonal bipyramid shape with idealized Cs (mirror) symmetry. The vanadium oxygen bond (157.2 pm) is typical for vanadyl(V). Two nitrate groups in the pentagonal plane are bidentate (V-O distances range from 199 to 206 pm). The third nitrate spans the pentagonal plane ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vanadyl Acetate
Vanadyl acetate is an inorganic chemical compound with the formula VO(CH3COO)2, which can be simplified to VO(OAc)2. It is a tan-colored solid, insoluble in water, that is used to produce other vanadyl acetate complexes such as with pyridine, urea, and thiourea. It also has been studied as a catalyst in the acetylation of alcohols. Production and structure Vanadyl acetate is produced by refluxing acetic anhydride with vanadium pentoxide Vanadium(V) oxide (''vanadia'') is the inorganic compound with the formula V2 O5. Commonly known as vanadium pentoxide, it is a dark yellow solid, although when freshly precipitated from aqueous solution, its colour is deep orange. Because of ... at 140 °C: :V2O5 + 3 (CH3CO)2O → 2 VO(CH3COO)2 + 2 CO2 + C2H6 This compound has a polymeric structure consisting of repeating VO6 octahedra. References {{Acetates Vanadium(IV) compounds Acetates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vanadyl Acetylacetonate
Vanadyl acetylacetonate is the chemical compound with the chemical formula, formula VO(acac)2, where acac– is the conjugate base of acetylacetone. It is a blue-green solid that dissolves in polar organic solvents. The complex (chemistry), coordination complex consists of the vanadyl ion, vanadyl group, VO2+, bound to two acac– ligands via the two oxygen atoms on each. Like other charge-neutral acetylacetonate complexes, it is not soluble in water. Synthesis The complex is generally prepared from vanadium(IV), e.g. vanadyl sulfate: :VOSO4 + 2 Hacac → VO(acac)2 + H2SO4 It can also be prepared by a redox reaction starting with vanadium pentoxide. In this reaction, some acetylacetone is oxidized to 2,3,4-Pentanetrione. Structure and properties The complex has a square pyramidal structure with a short V=O bond. This d1 compound is paramagnetic. Its optical spectrum exhibits two transitions. It is a weak Lewis acid, forming adducts with pyridine and methylamine. Applications ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vanadyl Chloride
Vanadium oxytrichloride is the inorganic compound with the formula VOCl3. This yellow distillable liquid hydrolyzes readily in air. It is an oxidizing agent. It is used as a reagent in organic synthesis. Samples often appear red or orange owing to an impurity of vanadium tetrachloride. Properties VOCl3 is a vanadium compound with vanadium in the +5 oxidation state and as such is diamagnetic. It is tetrahedral with O-V-Cl bond angles of 111° and Cl-V-Cl bond angles of 108°. The V-O and V-Cl bond lengths are 157 and 214 pm, respectively. VOCl3 is highly reactive toward water and evolves HCl upon standing. It is soluble in nonpolar solvents such as benzene, CH2Cl2, and hexane. In some aspects, the chemical properties of VOCl3 and POCl3 are similar. One distinction is that VOCl3 is a strong oxidizing agent, whereas the phosphorus compound is not. Neat VOCl3 is the usual chemical shift standard for 51V NMR spectroscopy. Preparation VOCl3 arises by the chlorination of V2O5 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vanadyl Perchlorate
Vanadyl perchlorate or vanadyl triperchlorate is a golden yellow coloured liquid or crystalline compound of vanadium, oxygen and perchlorate group. The substance consists of molecules covalently bound and is quite volatile; it ignites organic solvents on contact and explodes at temperatures above 80 °C. Formation Vanadyl perchlorate can be made by reacting vanadium pentoxide with dichlorine heptoxide at 5 °C. It is purified by distillation under a vacuum and recrystallisation at 21 °C. A solution of vanadium(V) perchlorate can be made by dissolving vanadium pentoxide in perchloric acid. The reaction of vanadium pentoxide and dichlorine hexoxide Dichlorine hexoxide is the chemical compound with the molecular formula or , which is correct for its gaseous state. However, in liquid or solid form, this chlorine oxide ionizes into the dark red ionic compound chloryl perchlorate or dioxochlor ... could produce VO(ClO4)3: : 2 V2O5 + 12 Cl2O6 → 4 VO(ClO4)3 + 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pervanadyl
Pervanadyl is jargon that has two meanings. *Pervanadyl can refer to aquo complexes containing (). This pale yellow oxycation of vanadium(V) is the predominant vanadium(V) species in acidic solutions with pH between 0 and 2. Like permanganate, pervanadate features the metal in its highest oxidation state. *Pervanadyl also can refer to peroxo derivatives of vanadium(V) which are often abbreviated . Several vanadium(V) peroxides have been characterized. The former are formed by protonation of vanadium(V) oxide in such solutions: : (''Equilibrium constant, K'' = ) The ion can form a complex with a single aminopolycarboxylate ligand, or with tridentate Schiff base ligands. The / redox couple is used at the cathode of the vanadium redox battery. The standard reduction potential of this couple is +1.00 V. See also * Vanadate References {{Vanadium compounds Vanadyl compounds Vanadium(V) compounds Oxycations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vanadium
Vanadium is a chemical element; it has Symbol (chemistry), symbol V and atomic number 23. It is a hard, silvery-grey, malleable transition metal. The elemental metal is rarely found in nature, but once isolated artificially, the formation of an oxide layer (passivation (chemistry), passivation) somewhat stabilizes the free metal against further oxidation. Spain, Spanish-Mexico, Mexican scientist Andrés Manuel del Río discovered compounds of vanadium in 1801 by analyzing a new lead-bearing mineral he called "brown lead". Though he initially presumed its qualities were due to the presence of a new element, he was later erroneously convinced by French chemist Hippolyte Victor Collet-Descotils that the element was just chromium. Then in 1830, Nils Gabriel Sefström generated chlorides of vanadium, thus proving there was a new element, and named it "vanadium" after the Scandinavian goddess of beauty and fertility, Vanadís (Freyja). The name was based on the wide range of colors fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vanadyl Fluoride
Vanadium(V) oxytrifluoride is a chemical compound with the formula V O F3. It is one of several vanadium(V) oxyhalides. VOF3 is a yellowish orange powder that is sensitive to moisture. Characteristic of early metal fluorides, the structure is polymeric in the solid state. The solid adopts a layered structure but upon evaporation, the species becomes dimeric. In contrast VOCl3 and VOBr3 remain tetrahedral in all states, being volatile liquids at room temperature. Reactions In organic synthesis, VOF3 is used for the oxidative coupling of phenols, for example in the syntheses of vancomycin and its analogues. For these applications VOF3 is typically dissolved in trifluoroacetic acid. Vanadium(V) oxytrifluoride reacts with hexamethyldisiloxane Hexamethyldisiloxane (HMDSO or MM) is an organosilicon compound with the formula O i(CH3)3. This volatile colourless liquid is used as a solvent and as a reagent in organic synthesis. It is prepared by the hydrolysis of trimethylsilyl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vanadyl Isopropoxide
Vanadyl isopropoxide is the metal alkoxide with the formula VO(O-iPr)3 (iPr = CH(CH3)2). A yellow volatile liquid, it is a common alkoxide of vanadium Vanadium is a chemical element; it has Symbol (chemistry), symbol V and atomic number 23. It is a hard, silvery-grey, malleable transition metal. The elemental metal is rarely found in nature, but once isolated artificially, the formation of an .... It is used as a reagent and as a precursor to vanadium oxides. The compound is diamagnetic. It is prepared by alcoholysis of vanadyl trichloride: :VOCl3 + 3 HOCH(CH3)2 → VO(OCH(CH3)2)3 + 3 HCl The related cyclopentanoxide VO(O-CH(CH2)4)3 is a dimer, one pair of alkoxide ligands bind weakly trans to the vanadyl oxygens. References {{Vanadium compounds Vanadium(V) compounds Alkoxides Vanadyl compounds Isopropyl compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentagonite
Pentagonite is a rare silicate mineral with formula Ca(VO)Si4O10·4(H2O). It was named for the unusual twinning called a fiveling with an apparent five-fold symmetry. It is a dimorph of cavansite. Pentagonite was first described in 1973 for an occurrence in Lake Owyhee State Park, Malheur County, Oregon. It has also been reported from the Pune district of India. It occurs as fracture and cavity fillings in tuff and basalt. It occurs with cavansite, heulandite, stilbite, analcime, apophyllite and calcite Calcite is a Carbonate minerals, carbonate mineral and the most stable Polymorphism (materials science), polymorph of calcium carbonate (CaCO3). It is a very common mineral, particularly as a component of limestone. Calcite defines hardness 3 on .... References Phyllosilicates Orthorhombic minerals Minerals in space group 36 Vanadium minerals Vanadyl compounds {{silicate-mineral-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cavansite
Cavansite, named for its chemical composition of ''calcium vanadium silicate'', is a deep blue hydrous calcium vanadium phyllosilicate mineral, occurring as a secondary mineral in basaltic and andesitic rocks along with a variety of zeolite minerals. Its blue coloring comes from vanadium, a metal ion. Discovered in 1967 in Malheur County, Oregon, cavansite is a relatively rare mineral. It is polymorphic with the even rarer mineral, pentagonite. It is most frequently found in Pune, India, and in the Deccan Traps, a large igneous province. Uses of cavansite Although cavansite contains vanadium, and could thus be a possible ore source for the element, it is not generally considered an ore mineral. However, because of its rich color and relative rarity, cavansite is a sought-after collector's mineral. Associated minerals * Members of the apophyllite group * Members of the zeolite group, particularly stilbite * babingtonite, Ca2 Fe2 Si5 O14 OH * quartz, Si O2 * ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
