Why Do Five Ga+ Cations Form a Ligand‐Stabilized [Ga5]5+ Pentagon and How Does a 5:1 Salt Pack in the Solid State?

The reaction of the Ga+ source [Ga(PhF)2]+[Al(ORF)4]− with the neutral σ‐donor ligand dmap (4‐Me2N‐C6H4N) produces the unexpectedly large and fivefold positively charged cluster cation salt [Ga5(dmap)10]5+([Al(ORF)4]−)5. It includes a regular and planar Ga5 pentagon with strong metal–metal bonding. Additionally, the compound represents the first salt in which an ionic 1:5 packing is realized. We discuss the nature of this structure which results from the conversion of the non‐bonding 4s2 lone‐pair orbitals into fully Ga‐Ga‐bonding orbitals and the solid‐state arrangement of the ions constituting the lattice as an almost orthohexagonal AX5 lattice, possibly the aristotype of any 5:1 salt. [ABSTRACT FROM AUTHOR]