Aromatic Ge56- ring as a robust building block in M6Ge5 and M12Ge10 (M = Li-Rb) clusters.

Aromatic Si56- rings have been established as persistent building blocks for lithium-silicon cluster-assembled materials, but the generality of this concept is unexplored. We investigate M6Ge5 monomers and M12Ge10 dimers (M = Li, Na, K, and Rb) using density functional theory. Across the alkali metal series, the lowest energy structures feature planar aromatic Ge56- rings that retain their geometry, bonding pattern, and π-aromaticity upon dimerization. In the M12Ge10 assemblies, each Ge56- ring sustains its own diatropic current (19.3-25.8 nA T-1) exceeding those of benzene and the cyclopentadienyl anion with intensities matching those of the corresponding monomers, demonstrating that the two rings remain electronically independent. Molecular dynamics simulations confirm kinetic stability. These results extend the aromatic-ring assembly strategy demonstrated for this family of gas-phase Ge56--based clusters across the full Li-Rb series.