Aluminium diboride (AlB
2) is a
chemical compound
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...
made from the metal
aluminium
Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. I ...
and the
metalloid boron. It is one of two compounds of aluminium and boron, the other being
AlB12, which are both commonly referred to as aluminium boride.
Structurally the B atoms form
graphite
Graphite () is a crystalline form of the element carbon. It consists of stacked layers of graphene. Graphite occurs naturally and is the most stable form of carbon under standard conditions. Synthetic and natural graphite are consumed on lar ...
-like sheets with Al atoms between them, and this is very similar to the structure of
magnesium diboride. Single crystals of AlB
2 exhibit metallic conductivity along the axis parallel to the basal hexagonal plane.
Aluminium boride is considered a hazardous substance as it reacts with
acids and
hydrogen
Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic ...
gas to produce toxic gases. For example, it reacts with hydrochloric acid to release
borane
Trihydridoboron, also known as borane or borine, is an unstable and highly reactive molecule with the chemical formula . The preparation of borane carbonyl, BH3(CO), played an important role in exploring the chemistry of boranes, as it indicated ...
and
aluminium chloride
Aluminium chloride, also known as aluminium trichloride, is an inorganic compound with the formula . It forms hexahydrate with the formula , containing six water molecules of hydration. Both are colourless crystals, but samples are often contam ...
.
The crystal structure of AlB
2 is often used as a prototype structure to describe
intermetallic compounds
An intermetallic (also called an intermetallic compound, intermetallic alloy, ordered intermetallic alloy, and a long-range-ordered alloy) is a type of metallic alloy that forms an ordered solid-state compound between two or more metallic eleme ...
. There are a large number of
structure types that fall within the AlB
2 structural family.
See also
*
Boride A boride is a compound between boron and a less electronegative element, for example silicon boride (SiB3 and SiB6). The borides are a very large group of compounds that are generally high melting and are covalent more than ionic in nature. Some bo ...
References
External links
"Boron"
Borides
Aluminium compounds
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