In this review, examples of borderline cases at the transition from “locally delocalized electrons” to delocalized electronic systems are summarized, with a special focus on examples that occur as anions in solution and in extended solids.   

Klein W., Schier A., Fässler T.F. (2021) Molecules Meet Solids: From Wade–Mingos Clusters to Intermetalloid Clusters. In: . Structure and Bonding. Springer, Berlin, Heidelberg.

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