The non-metals in the second period in the Periodic Table of the Elements appear as diatomic molecules: N2, O2 and F2. But there is no corresponding Ne2 molecule as the noble gases are monoatomic.

Justify based on the fully-labeled MO scheme of the (hypothetical) Ne2 molecule why the latter does not exist! Assume that the electronegativity of neon is as great as the one of elemental fluorine.

Can you now explain why the Xe2(2+) molecular cation exists (do so in a few sentences!)?

HINT: fully describe the bonding situation of the (hypothetical) Ne2 molecule by looking at the type of bond, the radical character as well as the magnetic behaviour and its bond order!