The Covalent Bond is the bond found usually between
non-metals, but can occur between non-metals and
metals. It is the result of constructive
interference between the
valence or outer shell electrons. This interference creates an are of high
probability for the electrons and hence creates an area of high electronegativity, which in turn attracts the two nuclei towards itself, forming the bond. And thus for many covalent bonds this results in uneven distribution of charge, creating
dipoles which allow for
hydrogen bonds. This is the case in
water.
Covalent bonding is successfully described with quantum physics, and the quantum model of the atom, unlike rutherfords solar system analogy or bohrs model.