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Silanes are saturated chemical compounds, which means that they consist of one or multiple silicon atoms linked to each other or one or multiple atoms of other chemical elements as the tetrahedral centers of multiple single bonds. By definition, cycles are excluded, so that the silanes comprise a homologous series of inorganic compounds with the general formula . Commercially available silanes are synthetically derived. Each silicon atom has four bonds (either Si-H or Si-Si bonds), and each hydrogen atom is joined to a silicon atom (H-Si bonds). A series of linked silicon atoms is known as the silicon skeleton or silicon backbone. The number of silicon atoms is used to define the size of the silane (e.g., Si2-silane). Related to silanes, is a homologous series of functional groups, side-chains or radicals with the general formula . Examples include silyl and disilanyl. The simplest possible silane (the parent molecule) is silane, . There is no limit to the number of silicon atoms that can be linked together, the only limitation being that the molecule is acyclic, is saturated, and is a hydrosilicon. Silanes are very reactive and have moderate biological activity. Much of the early work establishing that silicon does indeed form a homologous series of hydride analogous to the alkanes, albeit to a much smaller extent, was conducted by Alfred Stock and Carl Somiesky.〔E. Wiber, (Alfred Stock and the Renaissance of Inorganic Chemistry )," ''Pure & Appl. Chem.'', Vol. 49 (1977) pp. 691-700.〕 Although monosilane and disilane were already known, Stock and Somiesky discovered, beginning in 1916, the next four members of the SinH2n+2 series, up to n = 6, and they also documented the formation of solid phase polymeric silicon hydrides (see below).〔J. W. Mellor, "A Comprehensive Treatise on Inorganic and Theoretical Chemistry," Vol. VI, Longman, Green and Co. (1947) pp. 223 - 227.〕 Usually polymeric silanyl hydrides are based on silicone and thus called silicone hydrides (the back bone consists of Si-O-Si bonds). ==Structure classification== Saturated hydrosilicons can be: *linear (general formula Si''n''H2''n'' + 2) wherein the silicon atoms are joined in a snake-like structure *branched (general formula Si''n''H2''n'' + 2, ''n'' > 3) wherein the silicon backbone splits off in one or more directions *cyclic (general formula Si''n''H2''n'', ''n'' > 2) wherein the silicon backbone is linked so as to form a loop. According to the definition by IUPAC, the former two are silanes, whereas the third group is called cyclosilanes. Saturated hydrosilicons can also combine any of the linear, cyclic (e.g., polycyclic) and branching structures, and they are still silanes (no general formula) as long as they are acyclic (i.e., having no loops). They also have single covalent bonds between their silicons. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「silanes」の詳細全文を読む スポンサード リンク
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