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Binary Silicon-hydrogen Compounds
Silanes are saturated chemical compounds with the empirical formula SixHy. They are hydrosilanes, a class of compounds that includes compounds with Si-H and other Si-X bonds. All contain tetrahedral silicon and terminal hydrides. They only have Si–H and Si–Si single bonds. The bond lengths are 146.0 pm for a Si–H bond and 233 pm for a Si–Si bond. The structures of the silanes are analogues of the alkanes, starting with silane, , the analogue of methane, continuing with disilane , the analogue of ethane, etc. They are mainly of theoretical or academic interest. Inventory 132px, Cyclopentasilane is structurally similar to cyclopentane, just larger.">cyclopentane.html" ;"title="Cyclopentasilane is structurally similar to cyclopentane">Cyclopentasilane is structurally similar to cyclopentane, just larger. The simplest isomer of a silane is the one in which the silicon atoms are arranged in a single chain with no branches. This isomer is sometimes called the ''n'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disilane
Disilane is a chemical compound with chemical formula Si2H6 that was identified in 1902 by Henri Moissan and Samuel Smiles (1877–1953). Moissan and Smiles reported disilane as being among the products formed by the action of dilute acids on metal silicides. Although these reactions had been previously investigated by Friedrich Woehler and Heinrich Buff between 1857 and 1858, Moissan and Smiles were the first to explicitly identify disilane. They referred to disilane as ''silicoethane''. Higher members of the homologous series SinH2n+2 formed in these reactions were subsequently identified by Carl Somiesky (sometimes spelled "Karl Somieski") and Alfred Stock. At standard temperature and pressure, disilane is a colourless, acrid gas. Disilane and ethane have similar structures, although disilane is much more reactive. Other compounds of the general formula Si2X6 (X = hydride, halide, alkyl, aryl, and mixtures of these groups) are called disilanes. Disilane is a group 14 hydrid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentasilane
Silanes are saturated chemical compounds with the empirical formula SixHy. They are hydrosilanes, a class of compounds that includes compounds with Si-H and other Si-X bonds. All contain tetrahedral silicon and terminal hydrides. They only have Si–H and Si–Si single bonds. The bond lengths are 146.0 pm for a Si–H bond and 233 pm for a Si–Si bond. The structures of the silanes are analogues of the alkanes, starting with silane, , the analogue of methane, continuing with disilane , the analogue of ethane, etc. They are mainly of theoretical or academic interest. Inventory 132px, Cyclopentasilane is structurally similar to cyclopentane, just larger.">cyclopentane.html" ;"title="Cyclopentasilane is structurally similar to cyclopentane">Cyclopentasilane is structurally similar to cyclopentane, just larger. The simplest isomer of a silane is the one in which the silicon atoms are arranged in a single chain with no branches. This isomer is sometimes called the ''n''- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alfred Stock
Alfred Stock (July 16, 1876 – August 12, 1946) was a German inorganic chemist. He did pioneering research on the hydrides of boron and silicon, coordination chemistry, mercury, and mercury poisoning. The German Chemical Society's Alfred-Stock Memorial Prize is named after him. Life Stock was born in Danzig (Gdańsk) and educated at the Friedrich-Werder grammar school in Berlin. In 1894 he began studies in chemistry at the Friedrich Wilhelm-University in Berlin. After finishing his dissertation about the quantitative separation of arsenic and antimony in the works of Emil Fischer he got his doctoral degree. In 1899 he worked with the French chemist and toxicologist Henri Moissan in Paris for one year. He was given the task of synthesizing still unknown compounds of boron and silicon. Five years later he became professor at the University of Breslau. In 1916 he succeeded Richard Willstätter as director at the Kaiser Wilhelm Institute for Chemistry in Berlin. After a severe mercu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclopentasilane
Cyclopentasilane is a cyclic compound of silicon and hydrogen. Containing five silicon atoms arranged in a ring, it is the silicon analog of cyclopentane. Cyclopentasilane is a liquid oligosilane. It is of research interest because of its potential use as a liquid silicon ink for printing silicon structures on integrated circuits or solar cells. Production Cyclopentasilane can be made from diphenyldichlorosilane (C6H5)2SiCl2 reacting with lithium. This forms decaphenylcyclopentasilane. This reacts with aluminium chloride in benzene catalysed with hydrogen chloride to yield decachlorocyclopentasilane. Decachlorocyclopentasilane then has its chlorine replaced by hydrogen using lithium aluminium hydride. Properties Cyclopentasilane is pyrophoric. It has a σ-delocalization property. Cyclopentasilane is a liquid at standard conditions, but can be frozen to crystals at 173K. The monoclinic crystals are not isomorphic to cyclopentane. The silicon to silicon bond lengths in the solid var ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trisilane
Trisilane is the silane with the formula H2Si(SiH3)2. A liquid at standard temperature and pressure, it is a silicon analogue of propane. The contrast with propane however trisilane ignites spontaneously in air. Synthesis Trisilane was characterized by Alfred Stock having prepared it by the reaction of hydrochloric acid and magnesium silicide. This reaction had been explored as early as 1857 by Friedrich Woehler and Heinrich Buff, and further investigated by Henri Moissan and Samuel Smiles in 1902. Decomposition The key property of trisilane is its thermal lability. It degrades to silicon films and SiH4 according to this idealized equation: :Si3H8 → Si + 2 SiH4 In terms of mechanism, this decomposition proceeds by a 1,2 hydrogen shift that produces disilanes, normal and isotetrasilanes, and normal and isopentasilanes. Because it readily decomposes to leave films of Si, trisilane has been explored a means to apply thin layers of silicon for semiconductors and similar ap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silane
Silane is an inorganic compound with chemical formula, . It is a colourless, pyrophoric, toxic gas with a sharp, repulsive smell, somewhat similar to that of acetic acid. Silane is of practical interest as a precursor to elemental silicon. Silane with alkyl groups are effective water repellents for mineral surfaces such as concrete and masonry. Silanes with both organic and inorganic attachments are used as coupling agents. Production Commercial-scale routes Silane can be produced by several routes. Typically, it arises from the reaction of hydrogen chloride with magnesium silicide: : Mg2Si + 4 HCl -> 2 MgCl2 + SiH4 It is also prepared from metallurgical-grade silicon in a two-step process. First, silicon is treated with hydrogen chloride at about 300 °C to produce trichlorosilane, HSiCl3, along with hydrogen gas, according to the chemical equation : Si + 3 HCl -> HSiCl3 + H2 The trichlorosilane is then converted to a mixture of silane and silicon tetrachloride: : 4 HS ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cycloalkane
In organic chemistry, the cycloalkanes (also called naphthenes, but distinct from naphthalene) are the monocyclic saturated hydrocarbons. In other words, a cycloalkane consists only of hydrogen and carbon atoms arranged in a structure containing a single ring (possibly with side chains), and all of the carbon-carbon bonds are single. The larger cycloalkanes, with more than 20 carbon atoms are typically called ''cycloparaffins''. All cycloalkanes are isomers of alkenes. The cycloalkanes without side chains are classified as small (cyclopropane and cyclobutane), common (cyclopentane, cyclohexane, and cycloheptane), medium (cyclooctane through cyclotridecane), and large (all the rest). Besides this standard definition by the International Union of Pure and Applied Chemistry (IUPAC), in some authors' usage the term ''cycloalkane'' includes also those saturated hydrocarbons that are polycyclic. In any case, the general form of the chemical formula for cycloalkanes is C''n''H2(' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aryl
In organic chemistry, an aryl is any functional group or substituent derived from an aromatic ring, usually an aromatic hydrocarbon, such as phenyl and naphthyl. "Aryl" is used for the sake of abbreviation or generalization, and "Ar" is used as a placeholder for the aryl group in chemical structure diagrams, analogous to “R” used for any organic substituent. “Ar” is not to be confused with the elemental symbol for argon. A simple aryl group is phenyl (), a group derived from benzene. Examples of other aryl groups consist of: * The tolyl group () which is derived from toluene (methylbenzene) * The xylyl group (), which is derived from xylene (dimethylbenzene) * The naphthyl group (), which is derived from naphthalene Arylation is the process in which an aryl group is attached to a substituent. It is typically achieved by cross-coupling reactions. Nomenclature The most basic aryl group is phenyl, which is made up of a benzene ring with one hydrogen atom substituted ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkane
In organic chemistry, an alkane, or paraffin (a historical trivial name that also has other meanings), is an acyclic saturated hydrocarbon. In other words, an alkane consists of hydrogen and carbon atoms arranged in a tree structure in which all the carbon–carbon bonds are single. Alkanes have the general chemical formula . The alkanes range in complexity from the simplest case of methane (), where ''n'' = 1 (sometimes called the parent molecule), to arbitrarily large and complex molecules, like pentacontane () or 6-ethyl-2-methyl-5-(1-methylethyl) octane, an isomer of tetradecane (). The International Union of Pure and Applied Chemistry (IUPAC) defines alkanes as "acyclic branched or unbranched hydrocarbons having the general formula , and therefore consisting entirely of hydrogen atoms and saturated carbon atoms". However, some sources use the term to denote ''any'' saturated hydrocarbon, including those that are either monocyclic (i.e. the cycloalkanes) or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polysilicon Hydride
Polysilicon hydrides are polymers containing only silicon and hydrogen. They have the formula (SiH_)_ where 0.2 ≤ ''n'' ≤ 2.5 and ''x'' is the number of monomer units. The polysilicon hydrides are generally colorless or pale-yellow/ocher powders that are easily hydrolyzed and ignite readily in air. The surfaces of silicon prepared by MOCVD using silane (SiH4) consist of a polysilicon hydride. Synthesis Polysilicon hydrides are much less thermally stable than the corresponding alkanes (CnH2n+2). They are kinetically labile, with their decomposition reaction rate increasing with increases in the number of silicon atoms in the molecule. Consequently, the preparation and isolation of polysilicon hydrides is difficult for species containing more than a few silicon atoms. Greater catenation of the Si atoms can be obtained with the halides (Sin''X''2n+2 with n = 14) for the fluorides. Thus the polymeric silicon hydrides are formed along with smaller sili ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latin Language
Latin (, or , ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the Roman Republic it became the dominant language in the Italy (geographical region), Italian region and subsequently throughout the Roman Empire. Even after the Fall of the Western Roman Empire, fall of Western Rome, Latin remained the common language of international communication, science, scholarship and academia in Europe until well into the 18th century, when other regional vernaculars (including its own descendants, the Romance languages) supplanted it in common academic and political usage, and it eventually became a dead language in the modern linguistic definition. Latin is a fusional language, highly inflected language, with three distinct grammatical gender, genders (masculine, feminine, and neuter), six or seven ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IUPAC Numerical Multiplier
The numerical multiplier (or multiplying affix) in IUPAC nomenclature indicates how many particular atoms or functional groups are attached at a particular point in a molecule. The affixes are derived from both Latin and Greek. Compound affixes The prefixes are given from the least significant decimal digit up: units, then tens, then hundreds, then thousands. For example: :548 → octa- (8) + tetraconta- (40) + pentacta- (500) = ''octatetracontapentacta-'' :9267 → hepta- (7) + hexaconta- (60) + dicta- (200) + nonalia- (9000) = ''heptahexacontadictanonalia-'' The numeral one While the use of the affix ''mono-'' is rarely necessary in organic chemistry, it is often essential in inorganic chemistry to avoid ambiguity: carbon oxide could refer to either ''carbon monoxide'' or ''carbon dioxide''. In forming compound affixes, the numeral one is represented by the term ''hen-'' except when it forms part of the number eleven (''undeca-''): hence :241 → hen- (1) + tetraconta- (40) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
