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  2. Supramolecular chemistry - Wikipedia

    en.wikipedia.org/wiki/Supramolecular_chemistry

    Supramolecular chemistry refers to the branch of chemistry concerning chemical systems composed of a discrete number of molecules.The strength of the forces responsible for spatial organization of the system range from weak intermolecular forces, electrostatic charge, or hydrogen bonding to strong covalent bonding, provided that the electronic coupling strength remains small relative to the ...

  3. Covalent bond - Wikipedia

    en.wikipedia.org/wiki/Covalent_bond

    In organic chemistry, covalent bonding is much more common than ionic bonding. Covalent bonding also includes many kinds of interactions, including σ-bonding, π-bonding, metal-to-metal bonding, agostic interactions, bent bonds, three-center two-electron bonds and three-center four-electron bonds. [2] [3] The term covalent bond dates from 1939 ...

  4. Nitrogen rule - Wikipedia

    en.wikipedia.org/wiki/Nitrogen_rule

    This rule is derived from the fact that, perhaps coincidentally, for the most common chemical elements in neutral organic compounds (hydrogen, carbon, nitrogen, oxygen, silicon, phosphorus, sulfur, and the halogens), elements with even numbered nominal masses form even numbers of covalent bonds, while elements with odd numbered nominal masses form odd numbers of covalent bonds, with the ...

  5. Orbital hybridisation - Wikipedia

    en.wikipedia.org/wiki/Orbital_hybridisation

    In ethene, the two carbon atoms form a σ bond by overlapping one sp 2 orbital from each carbon atom. The π bond between the carbon atoms perpendicular to the molecular plane is formed by 2p–2p overlap. Each carbon atom forms covalent C–H bonds with two hydrogens by s–sp 2 overlap, all with 120° bond angles. The hydrogen–carbon bonds ...

  6. Chemical bond - Wikipedia

    en.wikipedia.org/wiki/Chemical_bond

    Molecules that are formed primarily from non-polar covalent bonds are often immiscible in water or other polar solvents, but much more soluble in non-polar solvents such as hexane. A polar covalent bond is a covalent bond with a significant ionic character. This means that the two shared electrons are closer to one of the atoms than the other ...

  7. Bent's rule - Wikipedia

    en.wikipedia.org/wiki/Bent's_rule

    The inductive effect is the transmission of charge through covalent bonds and Bent's rule provides a mechanism for such results via differences in hybridisation. In the table below, [ 26 ] as the groups bonded to the central carbon become more electronegative, the central carbon becomes more electron-withdrawing as measured by the polar ...

  8. Acceptor (semiconductors) - Wikipedia

    en.wikipedia.org/wiki/Acceptor_(semiconductors)

    When substituting for a silicon atom in the crystal lattice, the three valence electrons of boron form covalent bonds with three of the Si neighbours but the bond with the fourth remains unsatisfied. The initially electro-neutral acceptor becomes negatively charged . The unsatisfied bond attracts electrons from the neighbouring bonds.

  9. Fajans' rules - Wikipedia

    en.wikipedia.org/wiki/Fajans'_rules

    Although the bond in a compound like X+Y- may be considered to be 100% ionic, it will always have some degree of covalent character. When two oppositely charged ions (X+ and Y-) approach each other, the cation attracts electrons in the outermost shell of the anion but repels the positively charged nucleus.