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Indium Chalcogenides
The indium chalcogenides include all compounds of indium with the chalcogen elements, oxygen, sulfur, selenium and tellurium. (Polonium is excluded as little is known about its compounds with indium). The best-characterised compounds are the In(III) and In(II) chalcogenides e.g. the sulfides In2S3 and InS. This group of compounds has attracted a lot of research attention because they include semiconductors, photovoltaics and phase-change materials. In many applications indium chalcogenides are used as the basis of ternary and quaternary compounds such as indium tin oxide, ITO and copper indium gallium selenide, CIGS. Some compounds that were reported and have found their way into text books have not been substantiated by later researchers. The list of compounds below shows compounds that have been reported, and those compounds that have not had their structure determined, or whose existence has not been confirmed by the latest structural investigations, are in italics. There a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Compound
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element is therefore not a compound. A compound can be transformed into a different substance by a chemical reaction, which may involve interactions with other substances. In this process, bonds between atoms may be broken and/or new bonds formed. There are four major types of compounds, distinguished by how the constituent atoms are bonded together. Molecular compounds are held together by covalent bonds; ionic compounds are held together by ionic bonds; intermetallic compounds are held together by metallic bonds; coordination complexes are held together by coordinate covalent bonds. Non-stoichiometric compounds form a disputed marginal case. A chemical formula specifies the number of atoms of each element in a compound molecule, using the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indium Tin Oxide
Indium tin oxide (ITO) is a ternary composition of indium, tin and oxygen in varying proportions. Depending on the oxygen content, it can be described as either a ceramic or an alloy. Indium tin oxide is typically encountered as an oxygen-saturated composition with a formulation of 74% In, 18% Sn, and 8% O by weight. Oxygen-saturated compositions are so typical that unsaturated compositions are termed ''oxygen-deficient ITO''. It is transparent and colorless in thin layers, while in bulk form it is yellowish to gray. In the infrared region of the spectrum it acts as a metal-like mirror. Indium tin oxide is one of the most widely used transparent conducting oxides because of its electrical conductivity and optical transparency, the ease with which it can be deposited as a thin film, and its chemical resistance to moisture. As with all transparent conducting films, a compromise must be made between conductivity and transparency, since increasing the thickness and increasing the concent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indium Compounds
Indium is a chemical element with the symbol In and atomic number 49. Indium is the softest metal that is not an alkali metal. It is a silvery-white metal that resembles tin in appearance. It is a post-transition metal that makes up 0.21 parts per million of the Earth's crust. Indium has a melting point higher than sodium and gallium, but lower than lithium and tin. Chemically, indium is similar to gallium and thallium, and it is largely intermediate between the two in terms of its properties. Indium was discovered in 1863 by Ferdinand Reich and Hieronymous Theodor Richter by spectroscopic methods. They named it for the indigo blue line in its spectrum. Indium was isolated the next year. Indium is a minor component in zinc sulfide ores and is produced as a byproduct of zinc refinement. It is most notably used in the semiconductor industry, in low-melting-point metal alloys such as solders, in soft-metal high-vacuum seals, and in the production of transparent conductive coatings ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indium(III) Telluride
Indium(III) telluride ( In2 Te3) is a inorganic compound. A black solid, it is sometimes described as an intermetallic compound, because it has properties that are metal-like and salt like. It is a semiconductor that has attracted occasional interest for its thermoelectric and photovoltaic applications. No applications have been implemented commercially however. Preparation and reactions A conventional route entails heating the elements in a seal-tube: : Indium(III) telluride reacts with strong acids to produce hydrogen telluride Hydrogen telluride is the inorganic compound with the formula hydrogen, H2telluride (chemistry), Te. A hydrogen chalcogenide and the simplest hydride of tellurium, it is a colorless gas. Although unstable in ambient air, the gas can exist at very .... Further reading * * * References Tellurides Indium compounds Semiconductor materials {{inorganic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indium(III) Selenide
Indium(III) selenide is a compound of indium and selenium. It has potential for use in photovoltaic devices and it has been the subject of extensive research. The two most common phases, α and β, have a layered structure, while γ is a "defect wurtzite structure." In all, there are five known forms (α, β, γ, δ, κ). The α- β phase transition is accompanied by a change in electrical conductivity. The band-gap of γ-In2Se3 is approximately 1.9 eV. The crystalline form of a sample can depend on the method of production, for example thin films of pure γ-In2Se3 have been produced from trimethylindium, InMe3, and hydrogen selenide, H2Se, using MOCVD techniques. Indium selenide has been shown to have excellent electronic properties in its two-dimensional (few-layer) form. Because of its air sensitivity, several processes have been developed to encapsulate the material for the integration in electronic devices. See also *Gallium(III) selenide *Indium chalcogenides *Nanoparticle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N-type Semiconductor
An extrinsic semiconductor is one that has been '' doped''; during manufacture of the semiconductor crystal a trace element or chemical called a doping agent has been incorporated chemically into the crystal, for the purpose of giving it different electrical properties than the pure semiconductor crystal, which is called an ''intrinsic semiconductor''. In an extrinsic semiconductor it is these foreign dopant atoms in the crystal lattice that mainly provide the charge carriers which carry electric current through the crystal. The doping agents used are of two types, resulting in two types of extrinsic semiconductor. An ''electron donor'' dopant is an atom which, when incorporated in the crystal, releases a mobile conduction electron into the crystal lattice. An extrinsic semiconductor which has been doped with electron donor atoms is called an n-type semiconductor, because the majority of charge carriers in the crystal are negative electrons. An ''electron acceptor'' dopant is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indium(III) Sulfide
Indium(III) sulfide (Indium sesquisulfide, Indium sulfide (2:3), Indium (3+) sulfide) is the inorganic compound with the formula In2 S3. It has a "rotten egg" odor characteristic of sulfur compounds, and produces hydrogen sulfide gas when reacted with mineral acids. Three different structures (" polymorphs") are known: yellow, α-In2S3 has a defect cubic structure, red β-In2S3 has a defect spinel, tetragonal, structure, and γ-In2S3 has a layered structure. The red, β, form is considered to be the most stable form at room temperature, although the yellow form may be present depending on the method of production. In2S3 is attacked by acids and by sulfide. It is slightly soluble in Na2S.Indium Sulfide indium.com Indium sulfide was the first indium compound ever described, being reported in 1863. Reich and Richte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polytelluride
In chemistry, a polytelluride usually refers to anions of the formula (Ten)2-. Many main group and transition metals form complexes with polytelluride anions. Preparation Conceptually, polytellurides are derived from polytelluranes H2Ten, but such neutral species are not known (even H2Te is labile). Instead, analogous to the preparation of many Zintl ions, polytellurides are produced by reduction of elemental Te with alkali metals. Such reactions can be conducted by heating a mixture of the solids or by dissolving Te metal in amine solvents of alkali metals. Once generated, these alkali metal polytellurides can be converted to lipophilic salts by treatment cryptand ligands or by ion exchange with quat salts. Structures Salts of polytellurides have often been characterized by X-ray crystallography. Polytelluride salts generally feature open chains, which adopt a zig-zag conformation. In some cases, cyclic structures are observed as in Li2Te7, which features a square-plana ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isoelectronicity
Isoelectronicity is a phenomenon observed when two or more molecules have the same structure (positions and connectivities among atoms) and the same electronic configurations, but differ by what specific elements are at certain locations in the structure. For example, , , and are isoelectronic, while and = are not. This definition is sometimes termed ''valence isoelectronicity''. Definitions can sometimes be not as strict, sometimes requiring identity of the ''total'' electron count and with it the entire electronic configuration. More usually, definitions are broader, and may extend to allowing different numbers of atoms in the species being compared.A. A. Aradi & T. P. Fehlner, "Isoelectronic Organometallic Molecules", in F. G. A. Stone & Robert West (eds.) ''Advances in Organometallic Chemistry Vol. 30'' (1990), Chapter 5 (at p. 190google books link/ref> The importance of the concept lies in identifying significantly related species, as pairs or series. Isoelectronic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indium Halides
There are three sets of Indium halides, the trihalides, the monohalides, and several intermediate halides. In the monohalides the oxidation state of indium is +1 and their proper names are indium(I) fluoride, indium(I) chloride, indium(I) bromide and indium(I) iodide. The intermediate halides contain indium with oxidation states, +1, +2 and +3. Indium trihalides In all of the trihalides the oxidation state of indium is +3, and their proper names are indium(III) fluoride, indium(III) chloride, indium(III) bromide, and indium(III) iodide. The trihalides are Lewis acidic. Indium trichloride is a starting point in the production of trimethylindium which is used in the semiconductor industry. Indium(III) fluoride InF3 is a white solid, m.p. 1170 °C. Its structure contains 6 coordinate indium. Indium(III) chloride InCl3 is a white solid, m.p. 586 °C. It is obtained by oxidation of indium with chlorine. It is isostructural with AlCl3. Indium(III) bromide InB ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidation State
In chemistry, the oxidation state, or oxidation number, is the hypothetical charge of an atom if all of its bonds to different atoms were fully ionic. It describes the degree of oxidation (loss of electrons) of an atom in a chemical compound. Conceptually, the oxidation state may be positive, negative or zero. While fully ionic bonds are not found in nature, many bonds exhibit strong ionicity, making oxidation state a useful predictor of charge. The oxidation state of an atom does not represent the "real" formal charge on that atom, or any other actual atomic property. This is particularly true of high oxidation states, where the ionization energy required to produce a multiply positive ion is far greater than the energies available in chemical reactions. Additionally, the oxidation states of atoms in a given compound may vary depending on the choice of electronegativity scale used in their calculation. Thus, the oxidation state of an atom in a compound is purely a formalism. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper Indium Gallium Selenide
Copper indium gallium (di)selenide (CIGS) is a I- III- VI2 semiconductor material composed of copper, indium, gallium, and selenium. The material is a solid solution of copper indium selenide (often abbreviated "CIS") and copper gallium selenide. It has a chemical formula of CuIn1−''x''Ga''x''Se2, where the value of ''x'' can vary from 0 (pure copper indium selenide) to 1 (pure copper gallium selenide). CIGS is a tetrahedrally bonded semiconductor, with the chalcopyrite crystal structure, and a bandgap varying continuously with ''x'' from about 1.0 eV (for copper indium selenide) to about 1.7 eV (for copper gallium selenide). Structure CIGS is a tetrahedrally bonded semiconductor, with the chalcopyrite crystal structure. Upon heating it transforms to the zincblende form and the transition temperature decreases from 1045 °C for ''x'' = 0 to 805 °C for ''x'' = 1. Applications It is best known as the material for CIGS solar cells a thin-film technology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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