An anionic beryllium hydride dimer with an exceedingly short Be⋯Be distance.

Heteroleptic hydride complexes of the group 2 metals have seen considerable attention as Earth-abundant synthetic tools, yet anionic derivatives are exceedingly rare. We described the facile synthesis and in-depth characterisation of an anionic beryllium hydride dimer, featuring a dynamic [Be 2 H 3 ] cluster at its core with a short Be⋯Be distance. Despite this, there is no formal Be-Be bond in this complex, with only hydride bridging interactions leading to this remarkable structural attribute.