A pair of electrons not involved in bond formation.
Pair of electrons in the outer shell of an atom not involved in bonding.
a pair of electrons that is not used for bonding
Pair of electrons residing on one atom and not shared by other atoms; unshared pair.
a pair of electrons in a molecule which is not shared by two of the constituent atoms.
an electron pair that is localized on a given atom; an electron pair not involved in bonding.
A lone pair is an electron pair without bonding or sharing with other atoms. They are found in the outermost electron shell of an atom, so lone pairs are a subset of a molecule's valence electrons. They can be identified by examining the outermost energy level of an electron--lone electron pairs consist of paired electrons as opposed to single electrons, which may appear if the atomic orbital is not full.