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Ball-and-stick model of superconductor magnesium diboride. Boron atoms lie in hexagonal aromatic graphite-like layers, with a charge of −1 on each boron atom. Magnesium(II) ions lie between layers. Binary metal-boron compounds, the metal borides, contain only boron and a metal. They are metallic, very hard, with high melting points.
Various representations of bonding in borenium ions. [2]A borenium ion is an inorganic cation with the chemical formula [BR 2 L] +In this class of molecules, the electron-deficient boron center has two valence electrons involved in sigma bonding with two ligands, while the third ligand is a two-electron donor such that the overall charge of the complex is +1. [1]
Each boron atom has a formal −1 charge and magnesium is assigned a formal charge of +2. In this material, the boron centers are trigonal planar with an extra double bond for each boron, forming sheets akin to the carbon in graphite. However, unlike hexagonal boron nitride, which lacks electrons in the plane of the covalent atoms, the ...
Polymeric boron oxoanions are formed in aqueous solution of boric acid at pH 7–10 if the boron concentration is higher than about 0.025 mol/L. The best known of these is the tetraborate ion [B 4 O 7] 2−, found in the mineral borax: 4 [B(OH) 4] − + 2 H + ⇌ [B 4 O 5 (OH) 4] 2− + 7 H 2 O
Ion implantation setup with mass separator. Ion implantation equipment typically consists of an ion source, where ions of the desired element are produced, an accelerator, where the ions are electrostatically accelerated to a high energy or using radiofrequency, and a target chamber, where the ions impinge on a target, which is the material to be implanted.
Despite the low reactivity of the tetrafluoroborate anion in general, BF − 4 serves as a fluorine source to deliver an equivalent of fluoride. [2] The Balz–Schiemann reaction for the synthesis of aryl fluorides is the best known example of such a reaction. [3]
A lyate ion is a generic solvent molecule that has become a negative ion by loss of one or more protons. The -ate suffix also applies to negative fluoroanions, fluorides which have gained one or more protons and twice as many electrons. Tetrafluoroborate, BF − 4, is boron trifluoride, BF 3, which has gained one fluoride and two electrons.
Ball-and-stick model of the tetrahydroborate anion, [BH 4] −. Borohydride refers to the anion [B H 4] −, which is also called tetrahydridoborate, and its salts. [1] Borohydride or hydroborate is also the term used for compounds containing [BH 4−n X n] −, where n is an integer from 0 to 3, for example cyanoborohydride or cyanotrihydroborate [BH 3 (CN)] − and triethylborohydride or ...