It is known that most dianions are unbound per se, i.e. that the corresponding monoanions have negative electron affinities, and the "dianions" we see in e.g. metal oxides can exist as such only due to the additional positive charges (on top of the "weaker" positive charges on the e.g. oxygen cores) on the countercations' stabilising effect on the dianion's electrons, rendering them bound. It is also known that most neutral molecules are electronically bound; i.e. that the corresponding monocations have positive electron affinities.
However, some monoanions do have positive electron affinities- for example, the dodecahydrido-closo-dodecaborate dianion is bound, rendering its (radical) monoanion's electron affinity being positive.
My question now follows- are there any monocations with negative electron affinities; i.e. whose neutral counterparts are electronically unbound?