查看“︁氢化铍”︁的源代码

{{chembox
|   Name = 氢化铍（二氫化鈹）
|   ImageFile = Beryllium-hydride-3D-balls.png
|   ImageSize = 230px
|   ImageName = 
| Section1 = {{Chembox Identifiers
| CASNo = 7787-52-2
| CASNo_Ref = {{cascite|correct|CAS}}
|  PubChem  =  139073
|  InChI  =  1/Be.2H/rBeH2/h1H2
|  InChIKey  =  RWASOQSEFLDYLC-JICJMJRQAQ
|  ChEBI_Ref  = {{ebicite|correct|EBI}}|  ChEBI  =  33787
|  SMILES  =  [BeH2]
|  StdInChI_Ref  = {{stdinchicite|correct|chemspider}}|  StdInChI  =  1S/Be.2H
|  StdInChIKey_Ref  = {{stdinchicite|correct|chemspider}}|  StdInChIKey  =  RWASOQSEFLDYLC-UHFFFAOYSA-N
|  ChemSpiderID_Ref  = {{chemspidercite|correct|chemspider}}|  ChemSpiderID = 17215712   
}}
| Section2 = {{Chembox Properties
|   Formula = BeH<sub>2</sub>
|   MolarMass = 11.03 
|   Appearance = 白色无定形固体<ref name=G&E>{{Greenwood&Earnshaw}}, p. 115</ref>
|   Density = 0.65 g/cm<sup>3</sup>
|   Solubility = 遇水分解
|   MeltingPt = 250 °C (分解)<ref name=G&E/>
  }}
| Section3 = {{Chembox Structure
|   Structure = 
  }}
| Section8 = {{Chembox Related
|   OtherCations = 
|   OtherCpds = 
  }}
}}
'''氢化铍'''（BeH<sub>2</sub>）是[[铍]]的[[共价]][[氢化物]]<ref name="G&E"/>，因為有放熱量高，產生氣體體積大，[[比衝]]可到310秒等優點，常用于[[固態火箭發動機]]的[[燃料]]。<ref>{{cite journal zh | author = 谌晓洪, 朱正和, 高涛, 罗顺忠 | date = 2006年7月 | title = AlH<sub>n</sub> (n=1-3) 的分子結構及 AlH<sub>3</sub> 熱力學穩定性 | journal = 物理學報 | volume = 58 | issue = 1 | pages = 178-184 | url = http://wulixb.iphy.ac.cn/cn/ch/common/create_pdf.aspx?file_no=W20060738&year_id=2006&quarter_id=7&falg=1 | access-date = 2010-04-08 | archive-url = https://web.archive.org/web/20181017002005/http://wulixb.iphy.ac.cn/cn/ch/common/create_pdf.aspx?file_no=W20060738&year_id=2006&quarter_id=7&falg=1 | archive-date = 2018-10-17 | dead-url = yes }}</ref><ref>Pradyot Patnaik. ''Handbook of Inorganic Chemicals''. McGraw-Hill, 2002, ISBN 0070494398</ref><ref>{{cite book zh |author= 周濟平|coauthors= |title= 噴射發動機概論||format= |editor= |others= |edition= |location= |publisher= 中央圖書出版社|date= |pages= 159|accessdate= |id= 9576370701 }}</ref>

==合成==
最早在1951年通过[[二甲基铍]]与[[氢化铝锂]]反应得到。<ref>{{ cite journal en| author = Glenn D. Barbaras, Clyde Dillard, A. E. Finholt, Thomas Wartik, K. E. Wilzbach, and H. I. Schlesinger | year = 1951 | title = The Preparation of the Hydrides of Zinc, Cadmium, Beryllium, Magnesium and Lithium by the Use of Lithium Aluminum Hydride | journal = [[Journal of the American Chemical Society|J. Am. Chem. Soc.]] | volume = 73 | issue = 10 | pages = 4585–4590 | doi = 10.1021/ja01154a025 }}</ref>

:<math> \mathrm{2 \ Be(CH_3)_2 +  LiAlH_4 \rightarrow 2 \ BeH_2 + LiAl(CH_3)_4}</math>

纯氢化铍可由二叔丁基铍在210°C裂解而得。<ref>{{ cite journal en| author = G. E. Coates and F. Glockling | year = 1954 | title = Di-tert.-butylberyllium and beryllium hydride | journal = [[Journal of the Chemical Society|J. Chem. Soc.]] | pages = 2526–2529 | doi = 10.1039/JR9540002526 }}</ref> 如果用[[三苯基膦]]与[[硼氢化铍]]反应，则可得到纯度更高的氢化铍。<ref name=G&E/>

:<math> \mathrm{ Be(BH_4)_2 +  2 \ PPh_3 \rightarrow 2 \ Ph_3PBH_3 + BeH_2 }</math>

氢化铍无法利用单质化合的方法制备，这一点与其他碱土金属氢化物不同。<ref name = "Wiberg&Holleman">Egon Wiberg, Arnold Frederick Holleman (2001) ''Inorganic Chemistry'', Elsevier ISBN 0123526515, p. 1048</ref>

==特性==
氫化铍為白色固体，加熱至 240 度時會分解為铍及氫氣。氫化铍對濕氣敏感，不溶於大部份的有機溶劑，在水中會和水反應，產生[[氫氧化鈹]]和氫氣。

:<math> \mathrm{ BeH_2 + 2 \ H_2O \rightarrow \ Be (OH) _2 + 2 \ H_2 }</math>

==结构==
一般为无定形的白色固体。不过无定形体在0.5-2.5%[[氢化锂]]催化下加压加热时，也可得到高密度（~0.78 g/cm<sup>3</sup>）的[[六方晶系]]变体。<ref name="Brendel">{{ cite journal en| author = G. J. Brendel, E. M. Marlett, and L. M. Niebylski | year = 1978 | title = Crystalline beryllium hydride | journal = [[Inorganic Chemistry (journal)|Inorg. Chem.]] | | volume = 17 | issue = 12 | pages = 3589–3592 | doi = 10.1021/ic50190a051 }}</ref>

{{when|最近发现}}晶状 BeH<sub>2</sub> 的晶胞为体心斜方结构，具共角 BeH<sub>4</sub> 四面体相连而成的网状结构，而非以前认为的平面、由氢桥相连的无限长链结构。<ref>{{ cite journal en| author = Gordon S. Smith, Quintin C. Johnson, Deane K. Smith, D. E. Cox, Robert L. Snyder, Rong-Sheng Zhou and Allan Zalkin  | year = 1988 | title = The crystal and molecular structure of beryllium hydride | url = https://archive.org/details/sim_solid-state-communications_1988-08_67_5/page/491  | journal = [[Solid State Communications]]  | volume = 67 | issue = 5 | pages = 491–494 | doi = 10.1016/0038-1098(84)90168-6  }}</ref> 对无定形 BeH<sub>2</sub> 的研究也显示其为共角四面体相连的网状结构。<ref>{{ cite journal en| author = Sujatha Sampath, Kristina M. Lantzky, Chris J. Benmore, Jörg Neuefeind, and Joan E. Siewenie | year = 2003 | title = Structural quantum isotope effects in amorphous beryllium hydride  | journal = J. Chem. Phys. | volume = 119 | issue = | pages = 12499 | doi = 10.1063/1.1626638}}</ref>

BeH<sub>2</sub> 分子为直线型，Be-H 键长 133.376 pm。<ref>{{ cite journal en| author = Peter F. Bernath, Alireza Shayesteh, Keith Tereszchuk, Reginald Colin | year = 2002 | title = The Vibration-Rotation Emission Spectrum of Free BeH<sub>2</sub>  | journal = Science | volume = 297 | issue = 5585| pages = 1323–1324 | doi = 10.1126/science.1074580 }}</ref>

[[File:Beryllium-hydride-molecule-IR-3D-balls.png|150px|气相中氢化铍单体的球棍模型]]

==参见==
*[[氢化锂]]、[[氢化钙]]、[[硼烷]]
*[[氟化铍]]

==参考资料==
{{reflist}}
{{氫化物}}
{{鈹化合物}}
[[Category:铍化合物]]
[[Category:金属氢化物]]
[[Category:缺少物质图片的化学品条目]]
[[Category:1950年代发现的物质]]