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Copper(II) Thiocyanate
Copper(II) thiocyanate (or cupric thiocyanate) is a coordination polymer with formula Cu(SCN)2. It is a black solid which slowly decomposes in moist air. It was first reported in 1838 by Carl Ernst Claus and its structure was determined first in 2018. Structure The structure of Cu(SCN)2 was determined via powder X-ray diffraction and consists of chains of Cu(NCS)2 linked together by weak Cu-S-Cu bonds into two-dimensional layers. It can be considered a Jahn-Teller distorted analogue of the mercury thiocyanate structure-type. Each copper is octahedrally coordinated by four sulfurs and two nitrogens. The sulfur end of the SCN- ligand is doubly bridging. Synthesis Copper(II) thiocyanate can be prepared from the reaction of concentrated solutions of copper(II) and a soluble thiocyanate salt in water, precipitating as a black powder. With rapid drying, pure Cu(SCN)2 can be isolated. Reaction at lower concentrations and for longer periods of time generates instead copper(I) thiocya ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper(II) Bromide
Copper(II) bromide ( Cu Br2) is a chemical compound. It is used in photographic processing as an intensifier and as a brominating agent in organic synthesis. It is also used in the copper vapor laser, a class of laser where the medium is copper bromide vapour formed in-situ from hydrogen bromide reacting with the copper discharge tube. Producing yellow or green light, it is used in dermatological applications. Synthesis Copper(II) bromide can be obtained by combining copper oxide and hydrobromic acid: :CuO + 2HBr → CuBr2 + H2O. Purification Copper(II) bromide is purified by crystallization twice from water, filtration to remove any CuBr and concentration under vacuum. This product is dehydrated using phosphorus pentoxide. Molecular and crystal structure In the solid state CuBr2 has a polymeric structure, with CuBr4 planar units connected on opposite sides to form chains. The crystal structure is monoclinic, space group In mathematics, physics and chemistry, a space grou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper(II) Chloride
Copper(II) chloride is the chemical compound with the chemical formula CuCl2. The anhydrous form is yellowish brown but slowly absorbs moisture to form a blue-green dihydrate. Both the anhydrous and the dihydrate forms occur naturally as the very rare minerals tolbachite and eriochalcite, respectively.Marlene C. Morris, Howard F. McMurdie, Eloise H. Evans, Boris Paretzkin, Harry S. Parker, and Nicolas C. Panagiotopoulos (1981) ''Copper chloride hydrate (eriochalcite)'', in Standard X-ray Diffraction Powder PatternsNational Bureau of Standards, Monograph 25, Section 18; page 33. Structure Anhydrous CuCl2 adopts a distorted cadmium iodide structure. In this motif, the copper centers are octahedral. Most copper(II) compounds exhibit distortions from idealized octahedral geometry due to the Jahn-Teller effect, which in this case describes the localization of one d-electron into a molecular orbital that is strongly antibonding with respect to a pair of chloride ligands. In CuCl2·2H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper(I) Thiocyanate
Copper(I) thiocyanate (or cuprous thiocyanate) is a coordination polymer with formula CuSCN. It is an air-stable, white solid used as a precursor for the preparation of other thiocyanate salts. Structure At least two Polymorphism (materials science), polymorphs have been characterized by X-ray crystallography. They both feature copper(I) in a characteristic tetrahedral coordination geometry. The sulfur end of the SCN- ligand is triply bridging ligand, bridging so that the coordination sphere for copper is CuS3N.Smith, D. L.; Saunders, V. I. "Preparation and Structure Refinement of the 2H Polytype of beta-Copper(I) Thiocyanate" Acta Crystallographica B, 1982, volume 38, 907-909. Synthesis Copper(I) thiocyanate forms from the spontaneous decomposition of black copper(II) thiocyanate, releasing thiocyanogen, especially when heated. It is also formed from copper(II) thiocyanate under water, releasing (among others) thiocyanic acid and the highly poisonous hydrogen cyanide. It is c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cobalt(II) Thiocyanate
Cobalt(II) thiocyanate is an inorganic compound with the formula Co(SCN)2. It is a layered coordination complex and its trihydrate Co(SCN)2(H2O)3 is used in the cobalt thiocyanate test (or Scott test) for detecting cocaine. The test has been responsible for widespread false positives and false convictions. Structure and preparation left, 259x259px, Structure of Co(SCN)2(H2O)3. The structures of Co(SCN)2 and its hydrate Co(SCN)2(H2O)3 have been determined using X-ray crystallography. Co(SCN)2 forms infinite 2D sheets in the mercury(II) thiocyanate structure type, where as Co(SCN)2(H2O)3 consists of isolated tetrahedral Co(SCN)2(H2O)2 centers and one equivalent of water of crystallization. The hydrate may be prepared by the salt metathesis reactions, such as the reaction of aqueous cobalt(II) sulfate and barium thiocyanate to produce a barium sulfate precipitate, leaving the hydrate of Co(SCN)2 in solution: :CoSO4 + Ba(SCN)2 → BaSO4 + Co(SCN)2 or the reaction of the hexa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercury(II) Thiocyanate
Mercury(II) thiocyanate (Hg(SCN)2) is an inorganic chemical compound, the coordination complex of Hg2+ and the thiocyanate anion. It is a white powder. It will produce a large, winding "snake" when ignited, an effect known as the Pharaoh's serpent. Synthesis and structure The first synthesis of mercury thiocyanate was probably completed in 1821 by Jöns Jacob Berzelius: :HgO + 2 HSCN → Hg(SCN)2 + H2O Evidence for the first pure sample was presented in 1866 prepared by a chemist named Otto Hermes. It is prepared by treating solutions containing mercury(II) and thiocyanate ions. The low solubility product of mercury thiocyanate causes it to precipitate from the solution. Most syntheses are achieved by precipitation: :Hg(NO3)2 + 2 KSCN → Hg(SCN)2 + 2KNO3 The compound adopts a polymeric structure with Hg2+ centres linearly coordinated to two S atoms with a distance of 2.381 Å. Four weak Hg2+--N interactions are indicated with distances of 2.81 Å. Uses Mercury thiocyanate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonium Thiocyanate
Ammonium thiocyanate is an inorganic compound with the formula NH4SCN. It is the salt of the ammonium cation and the thiocyanate anion. Uses Ammonium thiocyanate is used in the manufacture of herbicides, thiourea, and transparent artificial resins; in matches; as a stabilizing agent in photography; in various rustproofing compositions; as an adjuvant in textile dyeing and printing; as a tracer in oil fields; in the separation of hafnium from zirconium (important for the production of hafnium-free zircalloy for use in nuclear fuel cladding), and in titrimetric analyses. In May 1945, USAAF General Victor E. Betrandias advanced a proposal to his superior General Arnold to use of ammonium thiocyanate to reduce rice crops in Japan as part of the bombing raids on their country. Ammonium thiocyanate can also be used to determine the iron content in soft drinks by colorimetry. Ammonium thiocyanate may also be used to separate quinidine, from liquors, after the isolation of quinine f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Thiocyanate
Potassium thiocyanate is the chemical compound with the molecular formula KSCN. It is an important salt of the thiocyanate anion, one of the pseudohalides. The compound has a low melting point relative to most other inorganic salts. Use in chemical synthesis Aqueous KSCN reacts almost quantitatively with Pb(NO3)2 to give Pb(SCN)2, which has been used to convert acyl chlorides to isothiocyanates. KSCN converts ethylene carbonate to ethylenesulfide. For this purpose, the KSCN is first melted under vacuum to remove water. In a related reaction, KSCN converts cyclohexene oxide to the corresponding episulfide. :C6H10O + KSCN → C6H10S + KOCN KSCN is also the starting product for the synthesis of carbonyl sulfide. Other uses Dilute aqueous KSCN is occasionally used for moderately realistic blood effects in film and theater. It can be painted onto a surface or kept as a colorless solution. When in contact with ferric chloride solution (or other solutions containing Fe3+), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coordination Polymer
A coordination polymer is an inorganic or organometallic polymer structure containing metal cation centers linked by ligands. More formally a coordination polymer is a coordination compound with repeating coordination entities extending in 1, 2, or 3 dimensions. It can also be described as a polymer whose repeat units are coordination complexes. Coordination polymers contain the subclass coordination networks that are coordination compounds extending, through repeating coordination entities, in 1 dimension, but with cross-links between two or more individual chains, loops, or spiro-links, or a coordination compound extending through repeating coordination entities in 2 or 3 dimensions. A subclass of these are the metal-organic frameworks, or MOFs, that are coordination networks with organic ligands containing potential voids. Coordination polymers are relevant to many fields, having many potential applications. Coordination polymers can be classified in a number of ways accor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karl Ernst Claus
Karl Ernst Claus (also Karl Klaus or Carl Claus, russian: Карл Ка́рлович Кла́ус, 22 January 1796 – 24 March 1864) was a German-Russian chemist and naturalist of Baltic German origin. Claus was a professor at Kazan State University and a member of the Russian Academy of Sciences. He was primarily known as a chemist and discoverer of the chemical element ruthenium, which he named after his homeland of Russia, but also as one of the first scientists who applied quantitative methods in botany.Клаус, Карл Карлович in Волков В.А. ''et al'' "Выдающиеся химики мира: Биографический справочник" Moscow, Высш. шк., 1991 (in Russian) Early life and education Karl Claus was born in ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jahn–Teller Effect
The Jahn–Teller effect (JT effect or JTE) is an important mechanism of spontaneous symmetry breaking in molecular and solid-state systems which has far-reaching consequences in different fields, and is responsible for a variety of phenomena in spectroscopy, stereochemistry, crystal chemistry, molecular and solid-state physics, and materials science. The effect is named for Hermann Arthur Jahn and Edward Teller, who first reported studies about it in 1937.Bunker, Philip R.; Jensen, Per (1998) ''Molecular Symmetry and Spectroscopy'' (2nd ed.). NRC Research Press, Ottaw/ref> Simplified overview The Jahn–Teller effect, sometimes also referred to as Jahn–Teller distortion, describes the geometrical distortion of molecules and ions that result from certain electron configurations. The Jahn–Teller theorem essentially states that any non-linear molecule with a spatially degenerate energy level, degenerate electronic ground state will undergo a geometrical distortion that removes th ... [...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 str ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper(I) Thiocyanate
Copper(I) thiocyanate (or cuprous thiocyanate) is a coordination polymer with formula CuSCN. It is an air-stable, white solid used as a precursor for the preparation of other thiocyanate salts. Structure At least two Polymorphism (materials science), polymorphs have been characterized by X-ray crystallography. They both feature copper(I) in a characteristic tetrahedral coordination geometry. The sulfur end of the SCN- ligand is triply bridging ligand, bridging so that the coordination sphere for copper is CuS3N.Smith, D. L.; Saunders, V. I. "Preparation and Structure Refinement of the 2H Polytype of beta-Copper(I) Thiocyanate" Acta Crystallographica B, 1982, volume 38, 907-909. Synthesis Copper(I) thiocyanate forms from the spontaneous decomposition of black copper(II) thiocyanate, releasing thiocyanogen, especially when heated. It is also formed from copper(II) thiocyanate under water, releasing (among others) thiocyanic acid and the highly poisonous hydrogen cyanide. It is c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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