First ionization energy and electron gain enthalpy of dihydrogen / stability comparison of dihydrogen ions [duplicate]

Stability of $$\ce{H2^{-}}<\ce{H2^{+}}<\ce{H2}$$

Stability of $$\ce{N2^{-}}<\ce{N2^{+}}<\ce{N2}$$

Source: Online lecture Etoosindia.

I am more concerned of $$\ce{H2^{-}}<\ce{H2^{+}}$$.

Does any satisfactory explanation exists (perhaps which can be generalized) for it? That is to add electron in anti-bonding molecular orbital more difficult than removing electron from bonding molecular orbital?

Observation indicates that First ionization energy of $$\ce{H2}$$ is greater than electron gain enthalpy (magnitude).

• Yes, that's a general rule that antibonding electrons "more antibonding" than bonding electrons are "bonding". – Mithoron Jun 10 at 12:57
• @Jay As Mithoron mentioned, this may help chemistry.stackexchange.com/questions/4517/… – Rishi Jun 10 at 13:18