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  2. Ammonia borane - Wikipedia

    en.wikipedia.org/wiki/Ammonia_borane

    The structure of the solid indicates a close association of the NH and the BH centers. The closest H−H distance is 1.990 Å, which can be compared with the H−H bonding distance of 0.74 Å. This interaction is called a dihydrogen bond. [10] [11] The original crystallographic analysis of this compound reversed the assignments of B and N.

  3. Lewis structure - Wikipedia

    en.wikipedia.org/wiki/Lewis_structure

    Lewis structures – also called Lewis dot formulas, Lewis dot structures, electron dot structures, or Lewis electron dot structures (LEDs) – are diagrams that show the bonding between atoms of a molecule, as well as the lone pairs of electrons that may exist in the molecule. [1][2][3] A Lewis structure can be drawn for any covalently bonded ...

  4. Lewis acids and bases - Wikipedia

    en.wikipedia.org/wiki/Lewis_acids_and_bases

    Acids and bases. A Lewis acid (named for the American physical chemist Gilbert N. Lewis) is a chemical species that contains an empty orbital which is capable of accepting an electron pair from a Lewis base to form a Lewis adduct. A Lewis base, then, is any species that has a filled orbital containing an electron pair which is not involved in ...

  5. Linnett double-quartet theory - Wikipedia

    en.wikipedia.org/wiki/Linnett_Double-Quartet_Theory

    Right: Simplified diagram of the LDQ structure of O 3, showing electrons in non-coincident pairs using thin lines and a coincident electron pair using a thick line. Linnett double-quartet theory (LDQ) is a method of describing the bonding in molecules which involves separating the electrons depending on their spin, placing them into separate ...

  6. Ammonia - Wikipedia

    en.wikipedia.org/wiki/Ammonia

    Molecular structure of ammonia and its three-dimensional shape. It has a net dipole moment of 1.484 D. Dot and cross structure of ammonia. The ammonia molecule has a trigonal pyramidal shape, as predicted by the valence shell electron pair repulsion theory (VSEPR theory) with an experimentally determined bond angle of 106.7°. [36]

  7. Pourbaix diagram - Wikipedia

    en.wikipedia.org/wiki/Pourbaix_diagram

    Pourbaix diagram of iron. [1] The Y axis corresponds to voltage potential. In electrochemistry, and more generally in solution chemistry, a Pourbaix diagram, also known as a potential/pH diagram, E H –pH diagram or a pE/pH diagram, is a plot of possible thermodynamically stable phases (i.e., at chemical equilibrium) of an aqueous electrochemical system.

  8. Dot and cross diagram - Wikipedia

    en.wikipedia.org/?title=Dot_and_cross_diagram&...

    Dot and cross diagram. Add languages. Add links. Article; Talk; English. Read; Edit; View history ... Text is available under the Creative Commons Attribution ...

  9. Sodium borohydride - Wikipedia

    en.wikipedia.org/wiki/Sodium_borohydride

    The stable phase at room temperature and pressure is α-NaBH 4, which is cubic and adopts an NaCl-type structure, in the Fm 3 m space group. At a pressure of 6.3 GPa, the structure changes to the tetragonal β-NaBH 4 (space group P42 1 c) and at 8.9 GPa, the orthorhombic γ-NaBH 4 (space group Pnma) becomes the most stable. [12] [13] [14]