Borides: Solid-State Chemistry
Borides: Solid-State Chemistry
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硼化物：固态化学
DOI：
10.1002/9781119951438.eibc0022.pub2
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
B. P. T. Fokwa
中科院分区：
文献类型：
--
作者：
B. P. T. Fokwa
硼与大多数其他元素形成化合物。除了与金属的许多二元和三元化合物--真正的硼化物--外，硼还与碳、硅、氮、磷、砷、氧、硫和硒形成了相关的化合物。这些相关化合物是由比硼更具电负性的元素形成的，因此不能表示为硼化物。然而，它们表现出与硼化物相似的性质和结构，因此被包括在本文中。这三组化合物都是介于小非金属原子和大金属原子之间的化合物。它们有时被称为间隙化合物，因为在富含金属的化合物中，较小的非金属原子通常占据金属原子之间的间隙。然而，在富硼化合物中，硼八面体或二十面体形成了一个连续的三维网络。大多数硼化物具有高熔点、极高硬度、脆性、高化学稳定性和对活性金属的高度惰性等特点。这些硼化物是非分子化合物，因此了解其晶体结构对表征硼化物相具有非常重要的意义。本文主要介绍了二元和三元硼化物的结构原理。目前已知的二元和三元硼化物至少有1000种，其中的化学键主要来自共价键、离子键和金属键，这就解释了硼化物的一些独特性质。通常，含硼比例较大的相是半导体，而含硼比例较低的相是金属导体。TiB_2和MgB_2(39 K以下的超导体)是良好的金属导体，而MeB_6相则是半导体或金属导体，具体取决于金属。有许多理论计算可用，特别是二硼化物，包括超导体MgB2。硼化物和相关化合物的用途主要基于它们的硬度、化学惰性和磁性和电学性质。这里可以举几个例子。在一些冶金过程中，使用B4C和立方氮化硼作为磨料，使用B4C和六硼化物作为表面涂层，使用CaB6作为脱氧剂。TiB2用于生产铝用汽化船。由于它对铝液具有较高的导电性和惰性，也可用于铝的工业生产过程。在室温下，Nd2Fe14B是已知最强的永磁材料。YB66大单晶用于单色同步辐射。
Boron forms compounds with most other elements. In addition to numerous binary and ternary compounds with metals—the true borides—boron forms related compounds with carbon, silicon, nitrogen, phosphorus, arsenic, oxygen, sulfur, and selenium. These related compounds are formed by elements more electronegative than boron and cannot therefore be denoted as borides. They display, however, similar properties and structures as borides, and are, therefore, included in this article.Borides are to some extent related to carbides and nitrides. All three groups of compounds are compounds between small nonmetal and larger metal atoms. They are occasionally denoted interstitial compounds, as the small nonmetal atoms often occupy the interstices between the metal atoms in metal‐rich compounds. In boron‐rich compounds, however, boron octahedra or icosahedra form a continuous three‐dimensional network. Most borides are characterized by high melting points, extreme hardness, brittleness, high chemical stability, and high inertness toward reactive metals.The borides are nonmolecular compounds and knowledge of the crystal structure is consequently of very high importance to characterize a boride phase. The structural principles of mainly the binary and ternary borides are described in this article. There are a total number of at least 1000 binary and ternary borides known at present.The chemical bonding in borides has evident contributions from covalent, ionic as well as metallic bonding, which explains some of the unique properties of the borides. As a rule, phases containing a large proportion of boron are semiconductors, whereas those with a lower proportion of boron are metallic conductors. TiB2and MgB2(superconductor below 39 K) are good metallic conductors, whereas MeB6phases are either semiconductors or metallic conductors depending on the metal. Many theoretical calculations are available, in particular of diborides, including the superconductor MgB2.The uses of borides and related compounds are mainly based on their hardness, chemical inertness, and magnetic and electrical properties. A few examples may be mentioned. B4C and cubic BN are used as abrasives, B4C and hexaborides as surface coatings, and CaB6as deoxidation agent in some metallurgical processes. TiB2is used in the production of vaporization boats for aluminum. It is also used in the industrial production process for aluminum owing to its high electrical conductivity and inertness toward liquid aluminum. Nd2Fe14B is, at room temperature, the strongest permanent magnetic material known. Large single crystals of YB66are used for monochromating synchrotron radiation.
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DOI：
--
发表时间：
2001
期刊：
影响因子：
--
作者：
S. Drechsler;H. Rosner;S. Shulga;H. Eschrig
通讯作者：
H. Eschrig
稀土-铁-硼材料：永磁体的新时代
DOI：
--
发表时间：
1986
期刊：
影响因子：
--
作者：
J. Herbst;R. W. Lee;F. Pinkerton
通讯作者：
F. Pinkerton
硼、硼化物及相关化合物：第 14 届硼、硼化物及相关化合物国际研讨会 (ISBB ’02) 论文集
DOI：
--
发表时间：
2004
期刊：
影响因子：
--
作者：
V. Gurin;M. Korsukova
通讯作者：
M. Korsukova
铝原子的 B4 四面体——τ-硼化物 Ni20 Al3 B6 和 Ni20 AlB14 中的令人惊讶的取代。
影响因子：
--
作者：
H. Hillebrecht;M. Ade
通讯作者：
M. Ade
巡回铁磁硼化物的位点优先设计：MRh6B3（M = Fe、Co）的实验和理论研究。
影响因子：
4.6
作者：
P. R. N. Misse;M. Gilleßen;B. Fokwa
通讯作者：
B. Fokwa