chemical bond

• chemical bond - “A sharing of valence electrons by atoms” (Timberlake, 2017)

  • (strong) intramolecular force
    • ionic bond (“completely polar bond”)
    • metallic bond
    • covalent bond
      • single, double or triple bond occurs when one (or two or three) pairs of electrons are shared.
      • polar covalent bond (electrons are shared unequally)
        • “A bond in which there are nonzero partial charges on the atoms” (Jones, 2016)
      • non-polar covalent bond (electrons are shared equally)
  • (weak) intermolecular force (IMF)
    • hydrogen bond (H-bond)
      • Dn−H···Ac
      • the strongest of the intermolecular forces
      • occurs when a hydrogen atom is covalently bonded to a highly electronegative atom (specifically $\mathrm{H},\mathrm{O},\mathrm{F}$)
    • van der Waals force
    • dipole-dipole interaction
      • interactions occur between polar molecules
    • ion-dipole
    • London dispersion force (LDF)
      • the weakest of the intermolecular forces

• ”completely nonpolar bond occurs when the electronegativities are identical and therefore possess a difference of zero” (Wikipedia)

• “The partial charges on the two atoms in a polar covalent bond form an electric dipole"

• "All bonds between atoms of different elements are polar to some extent.” (Jones, 2016)

• polarity of a bond:

  • $\Delta \chi \gtrsim 1.7$ → predominantly ionic bond
  • $0.4\lesssim \Delta \chi \lesssim 1.7$ → polar covalent bond
  • $\Delta \chi \lesssim 0.4$ → nonpolar covalent bond

• partial charge (or net atomic charge)

  • $\delta +$ and $\delta -$

• bond order

• bond length (or bond distance)

  • $\text{bond length: triple}<\text{double}<\text{single}$

• isomers

References

• Timberlake, Karen C. (2017). Chemistry: An Introduction to General, Organic, and Biological Chemistry. Pearson.
• Jones, Loretta (2016). Chemical Principles. W. H. Freeman.