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The elements in group 13 are also capable of forming stable compounds with the halogens, usually with the formula MX 3 (where M is a boron-group element and X is a halogen.) [14] Fluorine, the first halogen, is able to form stable compounds with every element that has been tested (except neon and helium), [15] and the boron group is no exception.
Enriched boron or 10 B is used in both radiation shielding and is the primary nuclide used in neutron capture therapy of cancer. In the latter ("boron neutron capture therapy" or BNCT), a compound containing 10 B is incorporated into a pharmaceutical which is selectively taken up by a malignant tumor and tissues near it.
The elements commonly classified as metalloids are boron, silicon, germanium, arsenic, antimony and tellurium. [ n 4 ] The status of polonium and astatine is not settled. Most authors recognise one or the other, or both, as metalloids; Herman, Hoffmann and Ashcroft, on the basis of relativistic modelling, predict astatine will be a monatomic metal.
Two earlier group number systems exist: CAS (Chemical Abstracts Service) and old IUPAC. Both use numerals (Arabic or Roman) and letters A and B. Both systems agree on the numbers. The numbers indicate approximately the highest oxidation number of the elements in that group, and so indicate similar chemistry with other elements with the same ...
A compound semiconductor is a semiconductor compound composed of chemical elements of at least two different species. These semiconductors form for example in periodic table groups 13–15 (old groups III–V), for example of elements from the Boron group (old group III, boron, aluminium, gallium, indium) and from group 15 (old group V, nitrogen, phosphorus, arsenic, antimony, bismuth).
Boron is found in nature on Earth almost entirely as various oxides of B(III), often associated with other elements. More than one hundred borate minerals contain boron in oxidation state +3. These minerals resemble silicates in some respect, although boron is often found not only in a tetrahedral coordination with oxygen, but also in a ...
The great variety of boranes show a huge covalent cluster chemistry, but the heavier group 13 hydrides do not. Despite their formulae, however, they tend to form polymers. Alane(aluminum trihydride) is a strong reducing agent with octahedrally coordinated aluminium atom
The main group metals, lanthanides and actinides form a wide variety of boron-rich borides, with metal:boron ratios up to YB 66. The properties of this group vary from one compound to the next, and include examples of compounds that are semi conductors, superconductors, diamagnetic, paramagnetic, ferromagnetic or anti-ferromagnetic. [1]