Real-space tools were employedt os how that the chemical bondings cenario used routinely to understand ground states lacks the necessaryf lexibility in excited states. It is shown that, even for two-center,t wo-electron bonds, the real-space bond orders have exotic values that have never been reported. The nature of these situationsw as uncovered by using electron-counting techniques that provide an appealing statistical interpretationo fb ondingd escrip-tors, together with simple physicalm odels. Bond orders greatert han one as well as negative bond ordersf or a single bonding electron pair emergei ns ituations in which the electrons in the pair show ag regarious (bosonic) instead of the usual lonely (fermionic) behavior.I nt he first case the gregariousp air is intra-atomic, whereas the coupling is interatomic in the second. An umber of examples are used to substantiate these claims.[a] J.
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