The term covalence in regard to bonding was first used in 1919 by Irving Langmuir in a Journal of the American Chemical Society article entitled "The Arrangement of Electrons in Atoms … See more

Bonds with one or three electrons can be found in radical species, which have an odd number of electrons. The simplest example of a 1-electron bond is found in the dihydrogen cation, H 2. One-electron bonds often have about half the bond energy of a 2 … See more

After the development of quantum mechanics, two basic theories were proposed to provide a quantum description of chemical bonding: See more

Atomic orbitals (except for s orbitals) have specific directional properties leading to different types of covalent bonds. Sigma (σ) bonds are the strongest covalent bonds and are due to head-on overlapping of orbitals on two different atoms. A single bond See more

There are several types of structures for covalent substances, including individual molecules, molecular structures, macromolecular structures and giant covalent structures. … See more

There are situations whereby a single Lewis structure is insufficient to explain the electron configuration in a molecule and its resulting … See more

An analogous effect to covalent binding is believed to occur in some nuclear systems, with the difference that the shared fermions are quarks rather than electrons. High energy proton-proton scattering cross-section indicates that quark interchange of … See more