Noble gas with one half-filled p-orbital from each F atom, resulting in a filled bonding orbital, a filled non-bonding orbital, and an empty antibonding orbital. The highest occupied molecular orbital is localized on the two terminal atoms. This represents a localization of charge which is facilitated by the high electronegativity of fluorine. The chemistries of the heavier noble gases, krypton and xenon, are well established. The chemistry of the lighter ones, argon and helium, is still at an early stage, while a neon compound is yet to be identified. The abundances of the noble gases in the universe decrease as their atomic
Noble gas compound century, their inertness was ascribed to a full valence shell of electrons which render them very chemically stable and nonreactive. All noble gases have full "s" and "p" outer electron shells (except helium, which has no "p" sublevel), and so do not form chemical compounds easily. Their high ionization energy and almost zero electron affinity explain their non-reactivity. In 1933, Linus Pauling predicted that the heavier noble gases would be able to form compounds with fluorine and oxygen. Specifically, he predicted the existence of krypton hexafluoride (KrF) and xenon hexafluoride (XeF), speculated that XeF might exist as an unstable compound,