Noble gas to be retained. Neon, argon, krypton, and xenon also form clathrate hydrates, where the noble gas is trapped in ice. Noble gases can form endohedral fullerene compounds, in which the noble gas atom is trapped inside a fullerene molecule. In 1993, it was discovered that when , a spherical molecule consisting of 60 carbon atoms, is exposed to noble gases at high pressure, complexes such as can be formed (the "@" notation indicates He is contained inside but not covalently bound to it). As of 2008, endohedral complexes with helium, neon, argon, krypton, and xenon have been obtained. These compounds
Noble gas noble gases. As a result of a full shell, the noble gases can be used in conjunction with the electron configuration notation to form the "noble gas notation". To do this, the nearest noble gas that precedes the element in question is written first, and then the electron configuration is continued from that point forward. For example, the electron notation of phosphorus is 1s 2s 2p 3s 3p, while the noble gas notation is [Ne] 3s 3p. This more compact notation makes it easier to identify elements, and is shorter than writing out the full notation of atomic orbitals. The