elektronijakoa

Elektronijakoa refers to the sharing of electron pairs between atoms that form covalent bonds. In covalent bonding, electrons are not owned by a single atom; instead each bond results from a pair of electrons that are largely localized in the region between the bonded nuclei, providing a more stable electronic arrangement.

Bond order indicates the number of shared electron pairs: a single bond shares one pair, a double bond shares two, and a triple bond shares three. Covalent bonds can be nonpolar when atomic electronegativities are similar, or polar when they differ, leading to partial charges. Some bonds, called coordinate or dative bonds, involve both electrons donated by one atom.

Theoretical descriptions vary. Valence bond theory emphasizes localized electron pairs and orbital overlap between two atoms; molecular orbital theory treats bonding electrons as delocalized in molecular orbitals that extend over the whole molecule. The bond strength and length depend on the degree of electron sharing and the energy gap between bonding and antibonding orbitals.

Common examples include the H2 molecule (one shared pair), O2 and N2 (double and triple bonds), and CH4 (four equivalent single bonds). Electron sharing also explains resonance in molecules such as CO2 and benzene, where electron density is distributed over multiple structures.

Elektronijakoa is a core concept in chemistry, influencing molecular geometry, reactivity, and spectroscopic properties, and it is studied through experimental techniques and quantum chemical calculations.