σ‐Aromaticity‐Induced Stabilization of Heterometallic Supertetrahedral Clusters [Zn₆Ge₁₆]⁴⁻ and [Cd₆Ge₁₆]⁴⁻

Abstract

In this work, the largest heterometallic supertetrahedral clusters, [Zn6Ge16]4− and [Cd6Ge16]4−, were directly self‐assembled through highly‐charged [Ge4]4− units and transition metal cations, in which 3‐center–2‐electron σ bonding in Ge2Zn or Ge2Cd triangles plays a vital role in the stabilization of the whole structure. The cluster structures have an open framework with a large central cavity of diameter 4.6 Å for Zn and 5.0 Å for Cd, respectively. Time‐dependent HRESI‐MS spectra show that the larger clusters grow from smaller components with a single [Ge4]4− and ZnMes2 units. Calculations performed at the DFT level indicate a very large HOMO–LUMO energy gap in [M6Ge16]4− (2.22 eV), suggesting high kinetic stability that may offer opportunities in materials science. These observations offer a new strategy for the assembly of heterometallic clusters with high symmetry.

Stabilizing hydrogen-mediated sextuple bonds by quintuple superatomic bonding and a bond

“…Besides, the cas (18,11) calculation on (Cp) 2 Ru 2 (μ-H) 4 (4) shows that the (1σ) 2 π 4 δ 4 (2σ) 2 (σ*) 2 (δ*) 4 configuration weights 96% of the total wavefunction, in accordance with the DFT result as well (see Fig. S13 † for the active-space molecular orbitals).…”

“…The chemistry of multiple bonding has been extensively studied in the last few decades, [1][2][3][4][5][6] especially after the first isolation of a salt containing the Re 2 Cl 8 2− ion in 1964, 7 which revealed a quadruple bond. Since then, a lot of compounds featuring quadruple bonding have been synthesized and characterized.…”