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  2. Boron - Wikipedia

    en.wikipedia.org/wiki/Boron

    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.

  3. File:Electron shell 005 Boron.svg - Wikipedia

    en.wikipedia.org/wiki/File:Electron_shell_005...

    Date/Time Thumbnail Dimensions User Comment; current: 11:57, 18 April 2006: 800 × 860 (1 KB): File Upload Bot (Pumbaa80) * '''Description:''' Electron shell diagram for Boron, the 5th element in the periodic table of elements.

  4. Allotropes of boron - Wikipedia

    en.wikipedia.org/wiki/Allotropes_of_boron

    Compressing boron above 160 GPa produces a boron phase with an as yet unknown structure. Contrary to other phases, which are semiconductors , this phase is a metal and becomes a superconductor with a critical temperature increasing from 6 K at 160 GPa to 11 K at 250 GPa. [ 48 ]

  5. Molecular orbital diagram - Wikipedia

    en.wikipedia.org/wiki/Molecular_orbital_diagram

    For a diatomic molecule, an MO diagram effectively shows the energetics of the bond between the two atoms, whose AO unbonded energies are shown on the sides. For simple polyatomic molecules with a "central atom" such as methane (CH 4) or carbon dioxide (CO 2), a MO diagram may show one of the identical bonds to the central atom. For other ...

  6. Boron compounds - Wikipedia

    en.wikipedia.org/wiki/Boron_compounds

    In the diamond-like structure, called cubic boron nitride (tradename Borazon), boron atoms exist in the tetrahedral structure of carbon atoms in diamond, but one in every four B-N bonds can be viewed as a coordinate covalent bond, wherein two electrons are donated by the nitrogen atom which acts as the Lewis base to a bond to the Lewis acidic ...

  7. Diborane - Wikipedia

    en.wikipedia.org/wiki/Diborane

    Bonding diagram of diborane (B 2 H 6) showing with curved lines a pair of three-center two-electron bonds, each of which consists of a pair of electrons bonding three atoms; two boron atoms and a hydrogen atom in the middle. The structure of diborane has D 2h symmetry. Four hydrides are terminal, while two bridge between the boron centers.

  8. Crystal structure of boron-rich metal borides - Wikipedia

    en.wikipedia.org/wiki/Crystal_structure_of_boron...

    The boron framework of YB 41 Si 1.2 can be described as a layered structure where two boron networks (figures 9a,b) stack along the z-axis. One boron network consists of 3 icosahedra I1, I2 and I3 and is located in the z = 0 plane; another network consists of the icosahedron I5 and the B 12 Si 3 polyhedron and lies at z = 0.5.

  9. Polyhedral skeletal electron pair theory - Wikipedia

    en.wikipedia.org/wiki/Polyhedral_skeletal...

    The boron atoms lie on each vertex of the octahedron and are sp hybridized. [11] One sp-hybrid radiates away from the structure forming the bond with the hydrogen atom. The other sp-hybrid radiates into the center of the structure forming a large bonding molecular orbital at the center of the cluster.